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  • 1904
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clever impostors could thrive equally well without troubling to study astronomy. The celebrated astrologers, however, were usually astronomers as well, and undoubtedly based many of their predictions on the position and movements of the heavenly bodies. Thus, the casting of a horoscope that is, the methods by which the astrologers ascertained the relative position of the heavenly bodies at the time of a birth–was a simple but fairly exact procedure. Its basis was the zodiac, or the path traced by the sun in his yearly course through certain constellations. At the moment of the birth of a child, the first care of the astrologer was to note the particular part of the zodiac that appeared on the horizon. The zodiac was then divided into “houses”–that is, into twelve spaces–on a chart. In these houses were inserted the places of the planets, sun, and moon, with reference to the zodiac. When this chart was completed it made a fairly correct diagram of the heavens and the position of the heavenly bodies as they would appear to a person standing at the place of birth at a certain time.

Up to this point the process was a simple one of astronomy. But the next step–the really important one–that of interpreting this chart, was the one which called forth the skill and imagination of the astrologer. In this interpretation, not in his mere observations, lay the secret of his success. Nor did his task cease with simply foretelling future events that were to happen in the life of the newly born infant. He must not only point out the dangers, but show the means whereby they could be averted, and his prophylactic measures, like his predictions, were alleged to be based on his reading of the stars.

But casting a horoscope at the time of births was, of course, only a small part of the astrologer’s duty. His offices were sought by persons of all ages for predictions as to their futures, the movements of an enemy, where to find stolen goods, and a host of everyday occurrences. In such cases it is more than probable that the astrologers did very little consulting of the stars in making their predictions. They became expert physiognomists and excellent judges of human nature, and were thus able to foretell futures with the same shrewdness and by the same methods as the modern “mediums,” palmists, and fortune-tellers. To strengthen belief in their powers, it became a common thing for some supposedly lost document of the astrologer to be mysteriously discovered after an important event, this document purporting to foretell this very event. It was also a common practice with astrologers to retain, or have access to, their original charts, cleverly altering them from time to time to fit conditions.

The dangers attendant upon astrology were of such a nature that the lot of the astrologer was likely to prove anything but an enviable one. As in the case of the alchemist, the greater the reputation of an astrologer the greater dangers he was likely to fall into. If he became so famous that he was employed by kings or noblemen, his too true or too false prophecies were likely to bring him into disrepute–even to endanger his life.

Throughout the dark age the astrologers flourished, but the sixteenth and seventeenth centuries were the golden age of these impostors. A skilful astrologer was as much an essential to the government as the highest official, and it would have been a bold monarch, indeed, who would undertake any expedition of importance unless sanctioned by the governing stars as interpreted by these officials.

It should not be understood, however, that belief in astrology died with the advent of the Copernican doctrine. It did become separated from astronomy very shortly after, to be sure, and undoubtedly among the scientists it lost much of its prestige. But it cannot be considered as entirely passed away, even to-day, and even if we leave out of consideration street-corner “astrologers” and fortune-tellers, whose signs may be seen in every large city, there still remains quite a large class of relatively intelligent people who believe in what they call “the science of astrology.” Needless to say, such people are not found among the scientific thinkers; but it is significant that scarcely a year passes that some book or pamphlet is not published by some ardent believer in astrology, attempting to prove by the illogical dogmas characteristic of unscientific thinkers that astrology is a science. The arguments contained in these pamphlets are very much the same as those of the astrologers three hundred years ago, except that they lack the quaint form of wording which is one of the features that lends interest to the older documents. These pamphlets need not be taken seriously, but they are interesting as exemplifying how difficult it is, even in an age of science, to entirely stamp out firmly established superstitions. Here are some of the arguments advanced in defence of astrology, taken from a little brochure entitled “Astrology Vindicated,” published in 1898: It will be found that a person born when the Sun is in twenty degrees Scorpio has the left ear as his exceptional feature and the nose (Sagittarius) bent towards the left ear. A person born when the Sun is in any of the latter degrees of Taurus, say the twenty-fifth degree, will have a small, sharp, weak chin, curved up towards Gemini, the two vertical lines on the upper lip.”[4] The time was when science went out of its way to prove that such statements were untrue; but that time is past, and such writers are usually classed among those energetic but misguided persons who are unable to distinguish between logic and sophistry.

In England, from the time of Elizabeth to the reign of William and Mary, judicial astrology was at its height. After the great London fire, in 1666, a committee of the House of Commons publicly summoned the famous astrologer, Lilly, to come before Parliament and report to them on his alleged prediction of the calamity that had befallen the city. Lilly, for some reason best known to himself, denied having made such a prediction, being, as he explained, “more interested in determining affairs of much more importance to the future welfare of the country.” Some of the explanations of his interpretations will suffice to show their absurdities, which, however, were by no means regarded as absurdities at that time, for Lilly was one of the greatest astrologers of his day. He said that in 1588 a prophecy had been printed in Greek characters which foretold exactly the troubles of England between the years 1641. and 1660. “And after him shall come a dreadful dead man,” ran the prophecy, “and with him a royal G of the best blood in the world, and he shall have the crown and shall set England on the right way and put out all heresies. His interpretation of this was that, “Monkery being extinguished above eighty or ninety years, and the Lord General’s name being Monk, is the dead man. The royal G or C (it is gamma in the Greek, intending C in the Latin, being the third letter in the alphabet) is Charles II., who, for his extraction, may be said to be of the best blood of the world.”[5]

This may be taken as a fair sample of Lilly’s interpretations of astrological prophesies, but many of his own writings, while somewhat more definite and direct, are still left sufficiently vague to allow his skilful interpretations to set right an apparent mistake. One of his famous documents was “The Starry Messenger,” a little pamphlet purporting to explain the phenomenon of a “strange apparition of three suns” that were seen in London on November 19, 1644—the anniversary of the birth of Charles I., then the reigning monarch. This phenomenon caused a great stir among the English astrologers, coming, as it did, at a time of great political disturbance. Prophecies were numerous, and Lilly’s brochure is only one of many that appeared at that time, most of which, however, have been lost. Lilly, in his preface, says: “If there be any of so prevaricate a judgment as to think that the apparition of these three Suns doth intimate no Novelle thing to happen in our own Climate, where they were manifestly visible, I shall lament their indisposition, and conceive their brains to be shallow, and voyde of understanding humanity, or notice of common History.”

Having thus forgiven his few doubting readers, who were by no means in the majority in his day, he takes up in review the records of the various appearances of three suns as they have occurred during the Christian era, showing how such phenomena have governed certain human events in a very definite manner. Some of these are worth recording.

“Anno 66. A comet was seen, and also three Suns: In which yeer, Florus President of the Jews was by them slain. Paul writes to Timothy. The Christians are warned by a divine Oracle, and depart out of Jerusalem. Boadice a British Queen, killeth seventy thousand Romans. The Nazareni, a scurvie Sect, begun, that boasted much of Revelations and Visions. About a year after Nero was proclaimed enemy to the State of Rome.”

Again, “Anno 1157, in September, there were seen three Suns together, in as clear weather as could be: And a few days after, in the same month, three Moons, and, in the Moon that stood in the middle, a white Crosse. Sueno, King of Denmark, at a great Feast, killeth Canutus: Sueno is himself slain, in pursuit of Waldemar. The Order of Eremites, according to the rule of Saint Augustine, begun this year; and in the next, the Pope submits to the Emperour: (was not this miraculous?) Lombardy was also adjudged to the Emperour.”

Continuing this list of peculiar phenomena he comes down to within a few years of his own time.

“Anno 1622, three Suns appeared at Heidelberg. The woful Calamities that have ever since fallen upon the Palatinate, we are all sensible of, and of the loss of it, for any thing I see, for ever, from the right Heir. Osman the great Turk is strangled that year; and Spinola besiegeth Bergen up Zoom, etc.”

Fortified by the enumeration of these past events, he then proceeds to make his deductions. “Only this I must tell thee,” he writes, “that the interpretation I write is, I conceive, grounded upon probable foundations; and who lives to see a few years over his head, will easily perceive I have unfolded as much as was fit to discover, and that my judgment was not a mile and a half from truth.”

There is a great significance in this “as much as was fit to discover”–a mysterious something that Lilly thinks it expedient not to divulge. But, nevertheless, one would imagine that he was about to make some definite prediction about Charles I., since these three suns appeared upon his birthday and surely must portend something concerning him. But after rambling on through many pages of dissertations upon planets and prophecies, he finally makes his own indefinite prediction.

“O all you Emperors, Kings, Princes, Rulers and Magistrates of Europe, this unaccustomed Apparition is like the Handwriting in Daniel to some of you; it premonisheth you, above all other people, to make your peace with God in time. You shall every one of you smart, and every one of you taste (none excepted) the heavie hand of God, who will strengthen your subjects with invincible courage to suppress your misgovernments and Oppressions in Church or Common-wealth; . . . Those words are general: a word for my own country of England. . . . Look to yourselves; here’s some monstrous death towards you. But to whom? wilt thou say. Herein we consider the Signe, Lord thereof, and the House; The Sun signifies in that Royal Signe, great ones; the House signifies captivity, poison, Treachery: From which is derived thus much, That some very great man, what King, Prince, Duke, or the like, I really affirm I perfectly know not, shall, I say, come to some such untimely end.”[6]

Here is shown a typical example of astrological prophecy, which seems to tell something or nothing, according to the point of view of the reader. According to a believer in astrology, after the execution of Charles I., five years later, this could be made to seem a direct and exact prophecy. For example, he says: “You Kings, Princes, etc., … it premonisheth you … to make your peace with God…. Look to yourselves; here’s some monstrous death towards you. … That some very great man, what King, Prince, . shall, I say, come to such untimely end.”

But by the doubter the complete prophecy could be shown to be absolutely indefinite, and applicable as much to the king of France or Spain as to Charles I., or to any king in the future, since no definite time is stated. Furthermore, Lilly distinctly states, “What King, Prince, Duke, or the like, I really affirm I perfectly know not”–which last, at least, was a most truthful statement. The same ingenuity that made “Gen. Monk” the “dreadful dead man,” could easily make such a prediction apply to the execution of Charles I. Such a definite statement that, on such and such a day a certain number of years in the future, the monarch of England would be beheaded–such an exact statement can scarcely be found in any of the works on astrology. It should be borne in mind, also, that Lilly was of the Cromwell party and opposed to the king.

After the death of Charles I., Lilly admitted that the monarch had given him a thousand pounds to cast his horoscope. “I advised him,” says Lilly, “to proceed eastwards; he went west, and all the world knows the result.” It is an unfortunate thing for the cause of astrology that Lilly failed to mention this until after the downfall of the monarch. In fact, the sudden death, or decline in power, of any monarch, even to-day, brings out the perennial post-mortem predictions of astrologers.

We see how Lilly, an opponent of the king, made his so-called prophecy of the disaster of the king and his army. At the same time another celebrated astrologer and rival of Lilly, George Wharton, also made some predictions about the outcome of the eventful march from Oxford. Wharton, unlike Lilly, was a follower of the king’s party, but that, of course, should have had no influence in his “scientific” reading of the stars. Wharton’s predictions are much less verbose than Lilly’s, much more explicit, and, incidentally, much more incorrect in this particular instance. “The Moon Lady of the 12,” he wrote, “and moving betwixt the 8 degree, 34 min., and 21 degree, 26 min. of Aquarius, gives us to understand that His Majesty shall receive much contentment by certain Messages brought him from foreign parts; and that he shall receive some sudden and unexpected supply of . . . by the means of some that assimilate the condition of his Enemies: And withal this comfort; that His Majesty shall be exceeding successful in Besieging Towns, Castles, or Forts, and in persuing the enemy.

“Mars his Sextile to the Sun, Lord of the Ascendant (which happeneth the 18 day of May) will encourage our Soldiers to advance with much alacrity and cheerfulness of spirit; to show themselves gallant in the most dangerous attempt…. And now to sum up all: It is most apparent to every impartial and ingenuous judgment; That although His Majesty cannot expect to be secured from every trivial disaster that may befall his army, either by the too much Presumption, Ignorance, or Negligence of some particular Persons (which is frequently incident and unavoidable in the best of Armies), yet the several positions of the Heavens duly considered and compared among themselves, as well in the prefixed Scheme as at the Quarterly Ingresses, do generally render His Majesty and his whole Army unexpectedly victorious and successful in all his designs; Believe it (London), thy Miseries approach, they are like to be many, great, and grievous, and not to be diverted, unless thou seasonably crave Pardon of God for being Nurse to this present Rebellion, and speedily submit to thy Prince’s Mercy; Which shall be the daily Prayer of Geo. Wharton.”[7]

In the light of after events, it is probable that Wharton’s stock as an astrologer was not greatly enhanced by this document, at least among members of the Royal family. Lilly’s book, on the other hand, became a favorite with the Parliamentary army.

After the downfall and death of Napoleon there were unearthed many alleged authentic astrological documents foretelling his ruin. And on the death of George IV., in 1830, there appeared a document (unknown, as usual, until that time) purporting to foretell the death of the monarch to the day, and this without the astrologer knowing that his horoscope was being cast for a monarch. A full account of this prophecy is told, with full belief, by Roback, a nineteenth-century astrologer. He says:

“In the year 1828, a stranger of noble mien, advanced in life, but possessing the most bland manners, arrived at the abode of a celebrated astrologer in London,” asking that the learned man foretell his future. “The astrologer complied with the request of the mysterious visitor, drew forth his tables, consulted his ephemeris, and cast the horoscope or celestial map for the hour and the moment of the inquiry, according to the established rules of his art.

“The elements of his calculation were adverse, and a feeling of gloom cast a shade of serious thought, if not dejection, over his countenance.

” ‘You are of high rank,’ said the astrologer, as he calculated and looked on the stranger, ‘and of illustrious title.’ The stranger made a graceful inclination of the head in token of acknowledgment of the complimentary remarks, and the astrologer proceeded with his mission.

“The celestial signs were ominous of calamity to the stranger, who, probably observing a sudden change in the countenance of the astrologer, eagerly inquired what evil or good fortune had been assigned him by the celestial orbs.

‘To the first part of your inquiry,’ said the astrologer, ‘I can readily reply. You have been a favorite of fortune; her smiles on you have been abundant, her frowns but few; you have had, perhaps now possess, wealth and power; the impossibility of their accomplishment is the only limit to the fulfilment of your desires.’ “

” ‘You have spoken truly of the past,’ said the stranger. ‘I have full faith in your revelations of the future: what say you of my pilgrimage in this life–is it short or long?’

” ‘I regret,’ replied the astrologer, in answer to this inquiry, ‘to be the herald of ill, though TRUE, fortune; your sojourn on earth will be short.’

” ‘How short?’ eagerly inquired the excited and anxious stranger.

” ‘Give me a momentary truce,’ said the astrologer; ‘I will consult the horoscope, and may possibly find some mitigating circumstances.’

“Having cast his eyes over the celestial map, and paused for some moments, he surveyed the countenance of the stranger with great sympathy, and said, ‘I am sorry that I can find no planetary influences that oppose your destiny–your death will take place in two years.’

“The event justified the astrologic prediction: George IV. died on May 18, 1830, exactly two years from the day on which he had visited the astrologer.”[8]

This makes a very pretty story, but it hardly seems like occult insight that an astrologer should have been able to predict an early death of a man nearly seventy years old, or to have guessed that his well-groomed visitor “had, perhaps now possesses, wealth and power.” Here again, however, the point of view of each individual plays the governing part in determining the importance of such a document. To the scientist it proves nothing; to the believer in astrology, everything. The significant thing is that it appeared shortly AFTER the death of the monarch.

On the Continent astrologers were even more in favor than in England. Charlemagne, and some of his immediate successors, to be sure, attempted to exterminate them, but such rulers as Louis XI. and Catherine de’ Medici patronized and encouraged them, and it was many years after the time of Copernicus before their influence was entirely stamped out even in official life. There can be no question that what gave the color of truth to many of the predictions was the fact that so many of the prophecies of sudden deaths and great conflagrations were known to have come true–in many instances were made to come true by the astrologer himself. And so it happened that when the prediction of a great conflagration at a certain time culminated in such a conflagration, many times a second but less-important burning took place, in which the ambitious astrologer, or his followers, took a central part about a stake, being convicted of incendiarism, which they had committed in order that their prophecies might be fulfilled.

But, on the other hand, these predictions were sometimes turned to account by interested friends to warn certain persons of approaching dangers.

For example, a certain astrologer foretold the death of Prince Alexander de’ Medici. He not only foretold the death, but described so minutely the circumstances that would attend it, and gave such a correct description of the assassin who should murder the prince, that he was at once suspected of having a hand in the assassination. It developed later, however, that such was probably not the case; but that some friend of Prince Alexander, knowing of the plot to take his life, had induced the astrologer to foretell the event in order that the prince might have timely warning and so elude the conspirators.

The cause of the decline of astrology was the growing prevalence of the new spirit of experimental science. Doubtless the most direct blow was dealt by the Copernican theory. So soon as this was established, the recognition of the earth’s subordinate place in the universe must have made it difficult for astronomers to be longer deceived by such coincidences as had sufficed to convince the observers of a more credulous generation. Tycho Brahe was, perhaps, the last astronomer of prominence who was a conscientious practiser of the art of the astrologer.



In the year 1526 there appeared a new lecturer on the platform at the University at Basel–a small, beardless, effeminate-looking person–who had already inflamed all Christendom with his peculiar philosophy, his revolutionary methods of treating diseases, and his unparalleled success in curing them. A man who was to be remembered in after-time by some as the father of modern chemistry and the founder of modern medicine; by others as madman, charlatan, impostor; and by still others as a combination of all these. This soft-cheeked, effeminate, woman-hating man, whose very sex has been questioned, was Theophrastus von Hohenheim, better known as Paracelsus (1493-1541).

To appreciate his work, something must be known of the life of the man. He was born near Maria-Einsiedeln, in Switzerland, the son of a poor physician of the place. He began the study of medicine under the instruction of his father, and later on came under the instruction of several learned churchmen. At the age of sixteen he entered the University of Basel, but, soon becoming disgusted with the philosophical teachings of the time, he quitted the scholarly world of dogmas and theories and went to live among the miners in the Tyrol, in order that he might study nature and men at first hand. Ordinary methods of study were thrown aside, and he devoted his time to personal observation–the only true means of gaining useful knowledge, as he preached and practised ever after. Here he became familiar with the art of mining, learned the physical properties of minerals, ores, and metals, and acquired some knowledge of mineral waters. More important still, he came in contact with such diseases, wounds, and injuries as miners are subject to, and he tried his hand at the practical treatment of these conditions, untrammelled by the traditions of a profession in which his training had been so scant.

Having acquired some empirical skill in treating diseases, Paracelsus set out wandering from place to place all over Europe, gathering practical information as he went, and learning more and more of the medicinal virtues of plants and minerals. His wanderings covered a period of about ten years, at the end of which time he returned to Basel, where he was soon invited to give a course of lectures in the university.

These lectures were revolutionary in two respects–they were given in German instead of time-honored Latin, and they were based upon personal experience rather than upon the works of such writers as Galen and Avicenna. Indeed, the iconoclastic teacher spoke with open disparagement of these revered masters, and openly upbraided his fellow-practitioners for following their tenets. Naturally such teaching raised a storm of opposition among the older physicians, but for a time the unparalleled success of Paracelsus in curing diseases more than offset his unpopularity. Gradually, however, his bitter tongue and his coarse personality rendered him so unpopular, even among his patients, that, finally, his liberty and life being jeopardized, he was obliged to flee from Basel, and became a wanderer. He lived for brief periods in Colmar, Nuremberg, Appenzell, Zurich, Pfeffers, Augsburg, and several other cities, until finally at Salzburg his eventful life came to a close in 1541. His enemies said that he had died in a tavern from the effects of a protracted debauch; his supporters maintained that he had been murdered at the instigation of rival physicians and apothecaries.

But the effects of his teachings had taken firm root, and continued to spread after his death. He had shown the fallibility of many of the teachings of the hitherto standard methods of treating diseases, and had demonstrated the advantages of independent reasoning based on observation. In his Magicum he gives his reasons for breaking with tradition. “I did,” he says, “embrace at the beginning these doctrines, as my adversaries (followers of Galen) have done, but since I saw that from their procedures nothing resulted but death, murder, stranglings, anchylosed limbs, paralysis, and so forth, that they held most diseases incurable. . . . therefore have I quitted this wretched art, and sought for truth in any other direction. I asked myself if there were no such thing as a teacher in medicine, where could I learn this art best? Nowhere better than the open book of nature, written with God’s own finger.” We shall see, however, that this “book of nature” taught Paracelsus some very strange lessons. Modesty was not one of these. “Now at this time,” he declares, “I, Theophrastus Paracelsus, Bombast, Monarch of the Arcana, was endowed by God with special gifts for this end, that every searcher after this supreme philosopher’s work may be forced to imitate and to follow me, be he Italian, Pole, Gaul, German, or whatsoever or whosoever he be. Come hither after me, all ye philosophers, astronomers, and spagirists. . . . I will show and open to you … this corporeal regeneration.”[1]

Paracelsus based his medical teachings on four “pillars” –philosophy, astronomy, alchemy, and virtue of the physician–a strange-enough equipment surely, and yet, properly interpreted, not quite so anomalous as it seems at first blush. Philosophy was the “gate of medicine,” whereby the physician entered rightly upon the true course of learning; astronomy, the study of the stars, was all-important because “they (the stars) caused disease by their exhalations, as, for instance, the sun by excessive heat”; alchemy, as he interpreted it, meant the improvement of natural substances for man’s benefit; while virtue in the physician was necessary since “only the virtuous are permitted to penetrate into the innermost nature of man and the universe.”

All his writings aim to promote progress in medicine, and to hold before the physician a grand ideal of his profession. In this his views are wide and far-reaching, based on the relationship which man bears to nature as a whole; but in his sweeping condemnations he not only rejected Galenic therapeutics and Galenic anatomy, but condemned dissections of any kind. He laid the cause of all diseases at the door of the three mystic elements–salt, sulphur, and mercury. In health he supposed these to be mingled in the body so as to be indistinguishable; a slight separation of them produced disease; and death he supposed to be the result of their complete separation. The spiritual agencies of diseases, he said, had nothing to do with either angels or devils, but were the spirits of human beings.

He believed that all food contained poisons, and that the function of digestion was to separate the poisonous from the nutritious. In the stomach was an archaeus, or alchemist, whose duty was to make this separation. In digestive disorders the archaeus failed to do this, and the poisons thus gaining access to the system were “coagulated” and deposited in the joints and various other parts of the body. Thus the deposits in the kidneys and tartar on the teeth were formed; and the stony deposits of gout were particularly familiar examples of this. All this is visionary enough, yet it shows at least a groping after rational explanations of vital phenomena.

Like most others of his time, Paracelsus believed firmly in the doctrine of “signatures”–a belief that every organ and part of the body had a corresponding form in nature, whose function was to heal diseases of the organ it resembled. The vagaries of this peculiar doctrine are too numerous and complicated for lengthy discussion, and varied greatly from generation to generation. In general, however, the theory may be summed up in the words of Paracelsus: “As a woman is known by her shape, so are the medicines.” Hence the physicians were constantly searching for some object of corresponding shape to an organ of the body. The most natural application of this doctrine would be the use of the organs of the lower animals for the treatment of the corresponding diseased organs in man. Thus diseases of the heart were to be treated with the hearts of animals, liver disorders with livers, and so on. But this apparently simple form of treatment had endless modifications and restrictions, for not all animals were useful. For example, it was useless to give the stomach of an ox in gastric diseases when the indication in such cases was really for the stomach of a rat. Nor were the organs of animals the only “signatures” in nature. Plants also played a very important role, and the herb-doctors devoted endless labor to searching for such plants. Thus the blood-root, with its red juice, was supposed to be useful in blood diseases, in stopping hemorrhage, or in subduing the redness of an inflammation.

Paracelsus’s system of signatures, however, was so complicated by his theories of astronomy and alchemy that it is practically beyond comprehension. It is possible that he himself may have understood it, but it is improbable that any one else did–as shown by the endless discussions that have taken place about it. But with all the vagaries of his theories he was still rational in his applications, and he attacked to good purpose the complicated “shot-gun” prescriptions of his contemporaries, advocating more simple methods of treatment.

The ever-fascinating subject of electricity, or, more specifically, “magnetism,” found great favor with him, and with properly adjusted magnets he claimed to be able to cure many diseases. In epilepsy and lockjaw, for example, one had but to fasten magnets to the four extremities of the body, and then, “when the proper medicines were given,” the cure would be effected. The easy loop-hole for excusing failure on the ground of improper medicines is obvious, but Paracelsus declares that this one prescription is of more value than “all the humoralists have ever written or taught.”

Since Paracelsus condemned the study of anatomy as useless, he quite naturally regarded surgery in the same light. In this he would have done far better to have studied some of his predecessors, such as Galen, Paul of Aegina, and Avicenna. But instead of “cutting men to pieces,” he taught that surgeons would gain more by devoting their time to searching for the universal panacea which would cure all diseases, surgical as well as medical. In this we detect a taint of the popular belief in the philosopher’s stone and the magic elixir of life, his belief in which have been stoutly denied by some of his followers. He did admit, however, that one operation alone was perhaps permissible–lithotomy, or the “cutting for stone.”

His influence upon medicine rests undoubtedly upon his revolutionary attitude, rather than on any great or new discoveries made by him. It is claimed by many that he brought prominently into use opium and mercury, and if this were indisputably proven his services to medicine could hardly be overestimated. Unfortunately, however, there are good grounds for doubting that he was particularly influential in reintroducing these medicines. His chief influence may perhaps be summed up in a single phrase–he overthrew old traditions.

To Paracelsus’s endeavors, however, if not to the actual products of his work, is due the credit of setting in motion the chain of thought that developed finally into scientific chemistry. Nor can the ultimate aim of the modern chemist seek a higher object than that of this sixteenth-century alchemist, who taught that “true alchemy has but one aim and object, to extract the quintessence of things, and to prepare arcana, tinctures, and elixirs which may restore to man the health and soundness he has lost.”


About the beginning of the sixteenth century, while Paracelsus was scoffing at the study of anatomy as useless, and using his influence against it, there had already come upon the scene the first of the great anatomists whose work was to make the century conspicuous in that branch of medicine.

The young anatomist Charles etienne (1503-1564) made one of the first noteworthy discoveries, pointing out for the first time that the spinal cord contains a canal, continuous throughout its length. He also made other minor discoveries of some importance, but his researches were completely overshadowed and obscured by the work of a young Fleming who came upon the scene a few years later, and who shone with such brilliancy in the medical world that he obscured completely the work of his contemporary until many years later. This young physician, who was destined to lead such an eventful career and meet such an untimely end as a martyr to science, was Andrew Vesalius (1514-1564), who is called the “greatest of anatomists.” At the time he came into the field medicine was struggling against the dominating Galenic teachings and the theories of Paracelsus, but perhaps most of all against the superstitions of the time. In France human dissections were attended with such dangers that the young Vesalius transferred his field of labors to Italy, where such investigations were covertly permitted, if not openly countenanced.

From the very start the young Fleming looked askance at the accepted teachings of the day, and began a series of independent investigations based upon his own observations. The results of these investigations he gave in a treatise on the subject which is regarded as the first comprehensive and systematic work on human anatomy. This remarkable work was published in the author’s twenty-eighth or twenty-ninth year. Soon after this Vesalius was invited as imperial physician to the court of Emperor Charles V. He continued to act in the same capacity at the court of Philip II., after the abdication of his patron. But in spite of this royal favor there was at work a factor more powerful than the influence of the monarch himself–an instrument that did so much to retard scientific progress, and by which so many lives were brought to a premature close.

Vesalius had received permission from the kinsmen of a certain grandee to perform an autopsy. While making his observations the heart of the outraged body was seen to palpitate–so at least it was reported. This was brought immediately to the attention of the Inquisition, and it was only by the intervention of the king himself that the anatomist escaped the usual fate of those accused by that tribunal. As it was, he was obliged to perform a pilgrimage to the Holy Land. While returning from this he was shipwrecked, and perished from hunger and exposure on the island of Zante.

At the very time when the anatomical writings of Vesalius were startling the medical world, there was living and working contemporaneously another great anatomist, Eustachius (died 1574), whose records of his anatomical investigations were ready for publication only nine years after the publication of the work of Vesalius. Owing to the unfortunate circumstances of the anatomist, however, they were never published during his lifetime–not, in fact, until 1714. When at last they were given to the world as Anatomical Engravings, they showed conclusively that Eustachius was equal, if not superior to Vesalius in his knowledge of anatomy. It has been said of this remarkable collection of engravings that if they had been published when they were made in the sixteenth century, anatomy would have been advanced by at least two centuries. But be this as it may, they certainly show that their author was a most careful dissector and observer.

Eustachius described accurately for the first time certain structures of the middle ear, and rediscovered the tube leading from the ear to the throat that bears his name. He also made careful studies of the teeth and the phenomena of first and second dentition. He was not baffled by the minuteness of structures and where he was unable to study them with the naked eye he used glasses for the purpose, and resorted to macerations and injections for the study of certain complicated structures. But while the fruit of his pen and pencil were lost for more than a century after his death, the effects of his teachings were not; and his two pupils, Fallopius and Columbus, are almost as well known to-day as their illustrious teacher. Columbus (1490-1559) did much in correcting the mistakes made in the anatomy of the bones as described by Vesalius. He also added much to the science by giving correct accounts of the shape and cavities of the heart, and made many other discoveries of minor importance. Fallopius (1523-1562) added considerably to the general knowledge of anatomy, made several discoveries in the anatomy of the ear, and also several organs in the abdominal cavity.

At this time a most vitally important controversy was in progress as to whether or not the veins of the bodies were supplied with valves, many anatomists being unable to find them. etienne had first described these structures, and Vesalius had confirmed his observations. It would seem as if there could be no difficulty in settling the question as to the fact of such valves being present in the vessels, for the demonstration is so simple that it is now made daily by medical students in all physiological laboratories and dissecting-rooms. But many of the great anatomists of the sixteenth century were unable to make this demonstration, even when it had been brought to their attention by such an authority as Vesalius. Fallopius, writing to Vesalius on the subject in 1562, declared that he was unable to find such valves. Others, however, such as Eustachius and Fabricius (1537-1619), were more successful, and found and described these structures. But the purpose served by these valves was entirely misinterpreted. That they act in preventing the backward flow of the blood in the veins on its way to the heart, just as the valves of the heart itself prevent regurgitation, has been known since the time of Harvey; but the best interpretation that could be given at that time, even by such a man as Fabricius, was that they acted in retarding the flow of the blood as it comes from the heart, and thus prevent its too rapid distribution throughout the body. The fact that the blood might have been going towards the heart, instead of coming from it, seems never to have been considered seriously until demonstrated so conclusively by Harvey.

Of this important and remarkable controversy over the valves in veins, Withington has this to say: “This is truly a marvellous story. A great Galenic anatomist is first to give a full and correct description of the valves and their function, but fails to see that any modification of the old view as to the motion of the blood is required. Two able dissectors carefully test their action by experiment, and come to a result. the exact reverse of the truth. Urged by them, the two foremost anatomists of the age make a special search for valves and fail to find them. Finally, passing over lesser peculiarities, an aged and honorable professor, who has lived through all this, calmly asserts that no anatomist, ancient or modern, has ever mentioned valves in veins till he discovered them in 1574!”[2]

Among the anatomists who probably discovered these valves was Michael Servetus (1511-1553); but if this is somewhat in doubt, it is certain that he discovered and described the pulmonary circulation, and had a very clear idea of the process of respiration as carried on in the lungs. The description was contained in a famous document sent to Calvin in 1545–a document which the reformer carefully kept for seven years in order that he might make use of some of the heretical statements it contained to accomplish his desire of bringing its writer to the stake. The awful fate of Servetus, the interesting character of the man, and the fact that he came so near to anticipating the discoveries of Harvey make him one of the most interesting figures in medical history.

In this document which was sent to Calvin, Servetus rejected the doctrine of natural, vital, and animal spirits, as contained in the veins, arteries, and nerves respectively, and made the all-important statement that the fluids contained in veins and arteries are the same. He showed also that the blood is “purged from fume” and purified by respiration in the lungs, and declared that there is a new vessel in the lungs, “formed out of vein and artery.” Even at the present day there is little to add to or change in this description of Servetus’s.

By keeping this document, pregnant with advanced scientific views, from the world, and in the end only using it as a means of destroying its author, the great reformer showed the same jealousy in retarding scientific progress as had his arch-enemies of the Inquisition, at whose dictates Vesalius became a martyr to science, and in whose dungeons etienne perished.


The time was ripe for the culminating discovery of the circulation of the blood; but as yet no one had determined the all-important fact that there are two currents of blood in the body, one going to the heart, one coming from it. The valves in the veins would seem to show conclusively that the venous current did not come from the heart, and surgeons must have observed thousands of times the every-day phenomenon of congested veins at the distal extremity of a limb around which a ligature or constriction of any kind had been placed, and the simultaneous depletion of the vessels at the proximal points above the ligature. But it should be remembered that inductive science was in its infancy. This was the sixteenth, not the nineteenth century, and few men had learned to put implicit confidence in their observations and convictions when opposed to existing doctrines. The time was at hand, however, when such a man was to make his appearance, and, as in the case of so many revolutionary doctrines in science, this man was an Englishman. It remained for William Harvey (1578-1657) to solve the great mystery which had puzzled the medical world since the beginning of history; not only to solve it, but to prove his case so conclusively and so simply that for all time his little booklet must he handed down as one of the great masterpieces of lucid and almost faultless demonstration.

Harvey, the son of a prosperous Kentish yeoman, was born at Folkestone. His education was begun at the grammar-school of Canterbury, and later he became a pensioner of Caius College, Cambridge. Soon after taking his degree of B.A., at the age of nineteen, he decided upon the profession of medicine, and went to Padua as a pupil of Fabricius and Casserius. Returning to England at the age of twenty-four, he soon after (1609) obtained the reversion of the post of physician to St. Bartholomew’s Hospital, his application being supported by James I. himself. Even at this time he was a popular physician, counting among his patients such men as Francis Bacon. In 1618 he was appointed physician extraordinary to the king, and, a little later, physician in ordinary. He was in attendance upon Charles I. at the battle of Edgehill, in 1642, where, with the young Prince of Wales and the Duke of York, after seeking shelter under a hedge, he drew a book out of his pocket and, forgetful of the battle, became absorbed in study, until finally the cannon-balls from the enemy’s artillery made him seek a more sheltered position.

On the fall of Charles I. he retired from practice, and lived in retirement with his brother. He was then well along in years, but still pursued his scientific researches with the same vigor as before, directing his attention chiefly to the study of embryology. On June 3, 1657, he was attacked by paralysis and died, in his eightieth year. He had lived to see his theory of the circulation accepted, several years before, by all the eminent anatomists of the civilized world.

A keenness in the observation of facts, characteristic of the mind of the man, had led Harvey to doubt the truth of existing doctrines as to the phenomena of the circulation. Galen had taught that “the arteries are filled, like bellows, because they are expanded,” but Harvey thought that the action of spurting blood from a severed vessel disproved this. For the spurting was remittant, “now with greater, now with less impetus,” and its greater force always corresponded to the expansion (diastole), not the contraction (systole) of the vessel. Furthermore, it was evident that contraction of the heart and the arteries was not simultaneous, as was commonly taught, because in that case there would be no marked propulsion of the blood in any direction; and there was no gainsaying the fact that the blood was forcibly propelled in a definite direction, and that direction away from the heart.

Harvey’s investigations led him to doubt also the accepted theory that there was a porosity in the septum of tissue that divides the two ventricles of the heart. It seemed unreasonable to suppose that a thick fluid like the blood could find its way through pores so small that they could not be demonstrated by any means devised by man. In evidence that there could be no such openings he pointed out that, since the two ventricles contract at the same time, this process would impede rather than facilitate such an intra-ventricular passage of blood. But what seemed the most conclusive proof of all was the fact that in the foetus there existed a demonstrable opening between the two ventricles, and yet this is closed in the fully developed heart. Why should Nature, if she intended that blood should pass between the two cavities, choose to close this opening and substitute microscopic openings in place of it? It would surely seem more reasonable to have the small perforations in the thin, easily permeable membrane of the foetus, and the opening in the adult heart, rather than the reverse. From all this Harvey drew his correct conclusions, declaring earnestly, “By Hercules, there ARE no such porosities, and they cannot be demonstrated.”

Having convinced himself that no intra-ventricular opening existed, he proceeded to study the action of the heart itself, untrammelled by too much faith in established theories, and, as yet, with no theory of his own. He soon discovered that the commonly accepted theory of the heart striking against the chest-wall during the period of relaxation was entirely wrong, and that its action was exactly the reverse of this, the heart striking the chest-wall during contraction. Having thus disproved the accepted theory concerning the heart’s action, he took up the subject of the action of arteries, and soon was able to demonstrate by vivisection that the contraction of the arteries was not simultaneous with contractions of the heart. His experiments demonstrated that these vessels were simply elastic tubes whose pulsations were “nothing else than the impulse of the blood within them.” The reason that the arterial pulsation was not simultaneous with the heart-beat he found to be because of the time required to carry the impulse along the tube,

By a series of further careful examinations and experiments, which are too extended to be given here, he was soon able further to demonstrate the action and course of the blood during the contractions of the heart. His explanations were practically the same as those given to-day–first the contraction of the auricle, sending blood into the ventricle; then ventricular contraction, making the pulse, and sending the blood into the arteries. He had thus demonstrated what had not been generally accepted before, that the heart was an organ for the propulsion of blood. To make such a statement to-day seems not unlike the sober announcement that the earth is round or that the sun does not revolve about it. Before Harvey’s time, however, it was considered as an organ that was “in some mysterious way the source of vitality and warmth, as an animated crucible for the concoction of blood and the generation of vital spirits.”[3]

In watching the rapid and ceaseless contractions of the heart, Harvey was impressed with the fact that, even if a very small amount of blood was sent out at each pulsation, an enormous quantity must pass through the organ in a day, or even in an hour. Estimating the size of the cavities of the heart, and noting that at least a drachm must be sent out with each pulsation, it was evident that the two thousand beats given by a very slow human heart in an hour must send out some forty pounds of blood–more than twice the amount in the entire body. The question was, what became of it all? For it should be remembered that the return of the blood by the veins was unknown, and nothing like a “circulation” more than vaguely conceived even by Harvey himself. Once it could be shown that the veins were constantly returning blood to the heart, the discovery that the blood in some way passes from the arteries to the veins was only a short step. Harvey, by resorting to vivisections of lower animals and reptiles, soon demonstrated beyond question the fact that the veins do carry the return blood. “But this, in particular, can be shown clearer than daylight,” says Harvey. “The vena cava enters the heart at an inferior portion, while the artery passes out above. Now if the vena cava be taken up with forceps or the thumb and finger, and the course of the blood intercepted for some distance below the heart, you will at once see it almost emptied between the fingers and the heart, the blood being exhausted by the heart’s pulsation, the heart at the same time becoming much paler even in its dilatation, smaller in size, owing to the deficiency of blood, and at length languid in pulsation, as if about to die. On the other hand, when you release the vein the heart immediately regains its color and dimensions. After that, if you leave the vein free and tie and compress the arteries at some distance from the heart, you will see, on the contrary, their included portion grow excessively turgid, the heart becoming so beyond measure, assuming a dark-red color, even to lividity, and at length so overloaded with blood as to seem in danger of suffocation; but when the obstruction is removed it returns to its normal condition, in size, color, and movement.”[4]

This conclusive demonstration that the veins return the blood to the heart must have been most impressive to Harvey, who had been taught to believe that the blood current in the veins pursued an opposite course, and must have tended to shake his faith in all existing doctrines of the day.

His next step was the natural one of demonstrating that the blood passes from the arteries to the veins. He demonstrated conclusively that this did occur, but for once his rejection of the ancient writers and one modern one was a mistake. For Galen had taught, and had attempted to demonstrate, that there are sets of minute vessels connecting the arteries and the veins; and Servetus had shown that there must be such vessels, at least in the lungs.

However, the little flaw in the otherwise complete demonstration of Harvey detracts nothing from the main issue at stake. It was for others who followed to show just how these small vessels acted in effecting the transfer of the blood from artery to vein, and the grand general statement that such a transfer does take place was, after all, the all-important one, and the exact method of how it takes place a detail. Harvey’s experiments to demonstrate that the blood passes from the arteries to the veins are so simply and concisely stated that they may best be given in his own words.

“I have here to cite certain experiments,” he wrote, “from which it seems obvious that the blood enters a limb by the arteries, and returns from it by the veins; that the arteries are the vessels carrying the blood from the heart, and the veins the returning channels of the blood to the heart; that in the limbs and extreme parts of the body the blood passes either by anastomosis from the arteries into the veins, or immediately by the pores of the flesh, or in both ways, as has already been said in speaking of the passage of the blood through the lungs; whence it appears manifest that in the circuit the blood moves from thence hither, and hence thither; from the centre to the extremities, to wit, and from the extreme parts back again to the centre. Finally, upon grounds of circulation, with the same elements as before, it will be obvious that the quantity can neither be accounted for by the ingesta, nor yet be held necessary to nutrition.

“Now let any one make an experiment on the arm of a man, either using such a fillet as is employed in blood-letting or grasping the limb tightly with his hand, the best subject for it being one who is lean, and who has large veins, and the best time after exercise, when the body is warm, the pulse is full, and the blood carried in large quantities to the extremities, for all then is more conspicuous; under such circumstances let a ligature be thrown about the extremity and drawn as tightly as can be borne: it will first be perceived that beyond the ligature neither in the wrist nor anywhere else do the arteries pulsate, that at the same time immediately above the ligature the artery begins to rise higher at each diastole, to throb more violently, and to swell in its vicinity with a kind of tide, as if it strove to break through and overcome the obstacle to its current; the artery here, in short, appears as if it were permanently full. The hand under such circumstances retains its natural color and appearances; in the course of time it begins to fall somewhat in temperature, indeed, but nothing is DRAWN into it.

“After the bandage has been kept on some short time in this way, let it be slackened a little, brought to the state or term of middling tightness which is used in bleeding, and it will be seen that the whole hand and arm will instantly become deeply suffused and distended, injected, gorged with blood, DRAWN, as it is said, by this middling ligature, without pain, or heat, or any horror of a vacuum, or any other cause yet indicated.

“As we have noted, in connection with the tight ligature, that the artery above the bandage was distended and pulsated, not below it, so, in the case of the moderately tight bandage, on the contrary, do we find that the veins below, never above, the fillet swell and become dilated, while the arteries shrink; and such is the degree of distention of the veins here that it is only very strong pressure that will force the blood beyond the fillet and cause any of the veins in the upper part of the arm to rise.

“From these facts it is easy for any careful observer to learn that the blood enters an extremity by the arteries; for when they are effectively compressed nothing is DRAWN to the member; the hand preserves its color; nothing flows into it, neither is it distended; but when the pressure is diminished, as it is with the bleeding fillet, it is manifest that the blood is instantly thrown in with force, for then the hand begins to swell; which is as much as to say that when the arteries pulsate the blood is flowing through them, as it is when the moderately tight ligature is applied; but when they do not pulsate, or when a tight ligature is used, they cease from transmitting anything; they are only distended above the part where the ligature is applied. The veins again being compressed, nothing can flow through them; the certain indication of which is that below the ligature they are much more tumid than above it, and than they usually appear when there is no bandage upon the arm.

“It therefore plainly appears that the ligature prevents the return of the blood through the veins to the parts above it, and maintains those beneath it in a state of permanent distention. But the arteries, in spite of the pressure, and under the force and impulse of the heart, send on the blood from the internal parts of the body to the parts beyond the bandage.”[5]

This use of ligatures is very significant, because, as shown, a very tight ligature stops circulation in both arteries and veins, while a loose one, while checking the circulation in the veins, which lie nearer the surface and are not so directly influenced by the force of the heart, does not stop the passage of blood in the arteries, which are usually deeply imbedded in the tissues, and not so easily influenced by pressure from without.

The last step of Harvey’s demonstration was to prove that the blood does flow along the veins to the heart, aided by the valves that had been the cause of so much discussion and dispute between the great sixteenth-century anatomists. Harvey not only demonstrated the presence of these valves, but showed conclusively, by simple experiments, what their function was, thus completing his demonstration of the phenomena of the circulation.

The final ocular demonstration of the passage of the blood from the arteries to the veins was not to be made until four years after Harvey’s death. This process, which can be observed easily in the web of a frog’s foot by the aid of a low-power lens, was first demonstrated by Marcello Malpighi (1628-1694) in 1661. By the aid of a lens he first saw the small “capillary” vessels connecting the veins and arteries in a piece of dried lung. Taking his cue from this, he examined the lung of a turtle, and was able to see in it the passage of the corpuscles through these minute vessels, making their way along these previously unknown channels from the arteries into the veins on their journey back to the heart. Thus the work of Harvey, all but complete, was made absolutely entire by the great Italian. And all this in a single generation.


The seventeenth century was not to close, however, without another discovery in science, which, when applied to the causation of disease almost two centuries later, revolutionized therapeutics more completely than any one discovery. This was the discovery of microbes, by Antonius von Leeuwenhoek (1632-1723), in 1683. Von Leeuwenhoek discovered that “in the white matter between his teeth” there were millions of microscopic “animals”–more, in fact, than “there were human beings in the united Netherlands,” and all “moving in the most delightful manner.” There can be no question that he saw them, for we can recognize in his descriptions of these various forms of little “animals” the four principal forms of microbes–the long and short rods of bacilli and bacteria, the spheres of micrococci, and the corkscrew spirillum.

The presence of these microbes in his mouth greatly annoyed Antonius, and he tried various methods of getting rid of them, such as using vinegar and hot coffee. In doing this he little suspected that he was anticipating modern antiseptic surgery by a century and three-quarters, and to be attempting what antiseptic surgery is now able to accomplish. For the fundamental principle of antisepsis is the use of medicines for ridding wounds of similar microscopic organisms. Von Leenwenhoek was only temporarily successful in his attempts, however, and took occasion to communicate his discovery to the Royal Society of England, hoping that they would be “interested in this novelty.” Probably they were, but not sufficiently so for any member to pursue any protracted investigations or reach any satisfactory conclusions, and the whole matter was practically forgotten until the middle of the nineteenth century.


Of the half-dozen surgeons who were prominent in the sixteenth century, Ambroise Pare (1517-1590), called the father of French surgery, is perhaps the most widely known. He rose from the position of a common barber to that of surgeon to three French monarchs, Henry II., Francis II., and Charles IX. Some of his mottoes are still first principles of the medical man. Among others are: “He who becomes a surgeon for the sake of money, and not for the sake of knowledge, will accomplish nothing”; and “A tried remedy is better than a newly invented.” On his statue is his modest estimate of his work in caring for the wounded, “Je le pansay, Dieu le guarit”–I dressed him, God cured him.

It was in this dressing of wounds on the battlefield that he accidentally discovered how useless and harmful was the terribly painful treatment of applying boiling oil to gunshot wounds as advocated by John of Vigo. It happened that after a certain battle, where there was an unusually large number of casualties, Pare found, to his horror, that no more boiling oil was available for the surgeons, and that he should be obliged to dress the wounded by other simpler methods. To his amazement the results proved entirely satisfactory, and from that day he discarded the hot-oil treatment.

As Pare did not understand Latin he wrote his treatises in French, thus inaugurating a custom in France that was begun by Paracelsus in Germany half a century before. He reintroduced the use of the ligature in controlling hemorrhage, introduced the “figure of eight” suture in the operation for hare-lip, improved many of the medico-legal doctrines, and advanced the practice of surgery generally. He is credited with having successfully performed the operation for strangulated hernia, but he probably borrowed it from Peter Franco (1505-1570), who published an account of this operation in 1556. As this operation is considered by some the most important operation in surgery, its discoverer is entitled to more than passing notice, although he was despised and ignored by the surgeons of his time.

Franco was an illiterate travelling lithotomist–a class of itinerant physicians who were very generally frowned down by the regular practitioners of medicine. But Franco possessed such skill as an operator, and appears to have been so earnest in the pursuit of what he considered a legitimate calling, that he finally overcame the popular prejudice and became one of the salaried surgeons of the republic of Bern. He was the first surgeon to perform the suprapubic lithotomy operation–the removal of stone through the abdomen instead of through the perineum. His works, while written in an illiterate style, give the clearest descriptions of any of the early modern writers.

As the fame of Franco rests upon his operation for prolonging human life, so the fame of his Italian contemporary, Gaspar Tagliacozzi (1545-1599), rests upon his operation for increasing human comfort and happiness by restoring amputated noses. At the time in which he lived amputation of the nose was very common, partly from disease, but also because a certain pope had fixed the amputation of that member as the penalty for larceny. Tagliacozzi probably borrowed his operation from the East; but he was the first Western surgeon to perform it and describe it. So great was the fame of his operations that patients flocked to him from all over Europe, and each “went away with as many noses as he liked.” Naturally, the man who directed his efforts to restoring structures that bad been removed by order of the Church was regarded in the light of a heretic by many theologians; and though he succeeded in cheating the stake or dungeon, and died a natural death, his body was finally cast out of the church in which it had been buried.

In the sixteenth century Germany produced a surgeon, Fabricius Hildanes (1560-1639), whose work compares favorably with that of Pare, and whose name would undoubtedly have been much better known had not the circumstances of the time in which he lived tended to obscure his merits. The blind followers of Paracelsus could see nothing outside the pale of their master’s teachings, and the disastrous Thirty Years’ War tended to obscure and retard all scientific advances in Germany. Unlike many of his fellow-surgeons, Hildanes was well versed in Latin and Greek; and, contrary to the teachings of Paracelsus, he laid particular stress upon the necessity of the surgeon having a thorough knowledge of anatomy. He had a helpmate in his wife, who was also something of a surgeon, and she is credited with having first made use of the magnet in removing particles of metal from the eye. Hildanes tells of a certain man who had been injured by a small piece of steel in the cornea, which resisted all his efforts to remove it. After observing Hildanes’ fruitless efforts for a time, it suddenly occurred to his wife to attempt to make the extraction with a piece of loadstone. While the physician held open the two lids, his wife attempted to withdraw the steel with the magnet held close to the cornea, and after several efforts she was successful–which Hildanes enumerates as one of the advantages of being a married man.

Hildanes was particularly happy in his inventions of surgical instruments, many of which were designed for locating and removing the various missiles recently introduced in warfare.

The seventeenth century, which was such a flourishing one for anatomy and physiology, was not as productive of great surgeons or advances in surgery as the sixteenth had been or the eighteenth was to be. There was a gradual improvement all along the line, however, and much of the work begun by such surgeons as Pare and Hildanes was perfected or improved. Perhaps the most progressive surgeon of the century was an Englishman, Richard Wiseman (1625-1686), who, like Harvey, enjoyed royal favor, being in the service of all the Stuart kings. He was the first surgeon to advocate primary amputation, in gunshot wounds, of the limbs, and also to introduce the treatment of aneurisms by compression; but he is generally rated as a conservative operator, who favored medication rather than radical operations, where possible.

In Italy, Marcus Aurelius Severinus (1580-1656) and Peter Marchettis (1589-1675) were the leading surgeons of their nation. Like many of his predecessors in Europe, Severinus ran amuck with the Holy Inquisition and fled from Naples. But the waning of the powerful arm of the Church is shown by the fact that he was brought back by the unanimous voice of the grateful citizens, and lived in safety despite the frowns of the theologians.

The sixteenth century cannot be said to have added much of importance in the field of practical medicine, and, as in the preceding and succeeding centuries, was at best only struggling along in the wake of anatomy, physiology, and surgery. In the seventeenth century, however, at least one discovery in therapeutics was made that has been an inestimable boon to humanity ever since. This was the introduction of cinchona bark (from which quinine is obtained) in 1640. But this century was productive of many medical SYSTEMS, and could boast of many great names among the medical profession, and, on the whole, made considerably more progress than the preceding century.

Of the founders of medical systems, one of the most widely known is Jan Baptista van Helmont (1578-1644), an eccentric genius who constructed a system of medicine of his own and for a time exerted considerable influence. But in the end his system was destined to pass out of existence, not very long after the death of its author. Van Helmont was not only a physician, but was master of all the other branches of learning of the time, taking up the study of medicine and chemistry as an after-thought, but devoting himself to them with the greatest enthusiasm once he had begun his investigations. His attitude towards existing doctrines was as revolutionary as that of Paracelsus, and he rejected the teachings of Galen and all the ancient writers, although retaining some of the views of Paracelsus. He modified the archaeus of Paracelsus, and added many complications to it. He believed the whole body to be controlled by an archaeus influus, the soul by the archaei insiti, and these in turn controlled by the central archeus. His system is too elaborate and complicated for full explanation, but its chief service to medicine was in introducing new chemical methods in the preparation of drugs. In this way he was indirectly connected with the establishment of the Iatrochemical school. It was he who first used the word “gas”–a word coined by him, along with many others that soon fell into disuse.

The principles of the Iatrochemical school were the use of chemical medicines, and a theory of pathology different from the prevailing “humoral” pathology. The founder of this school was Sylvius (Franz de le Boe, 1614-1672), professor of medicine at Leyden. He attempted to establish a permanent system of medicine based on the newly discovered theory of the circulation and the new chemistry, but his name is remembered by medical men because of the fissure in the brain (fissure of Sylvius) that bears it. He laid great stress on the cause of fevers and other diseases as originating in the disturbances of the process of fermentation in the stomach. The doctrines of Sylvius spread widely over the continent, but were not generally accepted in England until modified by Thomas Willis (1622-1675), whose name, like that of Sylvius, is perpetuated by a structure in the brain named after him, the circle of Willis. Willis’s descriptions of certain nervous diseases, and an account of diabetes, are the first recorded, and added materially to scientific medicine. These schools of medicine lasted until the end of the seventeenth century, when they were finally overthrown by Sydenham.

The Iatrophysical school (also called iatromathematical, iatromechanical, or physiatric) was founded on theories of physiology, probably by Borelli, of Naples (1608-1679), although Sanctorius; Sanctorius, a professor at Padua, was a precursor, if not directly interested in establishing it. Sanctorius discovered the fact that an “insensible perspiration” is being given off by the body continually, and was amazed to find that loss of weight in this way far exceeded the loss of weight by all other excretions of the body combined. He made this discovery by means of a peculiar weighing-machine to which a chair was attached, and in which he spent most of his time. Very naturally he overestimated the importance of this discovery, but it was, nevertheless, of great value in pointing out the hygienic importance of the care of the skin. He also introduced a thermometer which he advocated as valuable in cases of fever, but the instrument was probably not his own invention, but borrowed from his friend Galileo.

Harvey’s discovery of the circulation of the blood laid the foundation of the Iatrophysical school by showing that this vital process was comparable to a hydraulic system. In his On the Motive of Animals, Borelli first attempted to account for the phenomena of life and diseases on these principles. The iatromechanics held that the great cause of disease is due to different states of elasticity of the solids of the body interfering with the movements of the fluids, which are themselves subject to changes in density, one or both of these conditions continuing to cause stagnation or congestion. The school thus founded by Borelli was the outcome of the unbounded enthusiasm, with its accompanying exaggeration of certain phenomena with the corresponding belittling of others that naturally follows such a revolutionary discovery as that of Harvey. Having such a founder as the brilliant Italian Borelli, it was given a sufficient impetus by his writings to carry it some distance before it finally collapsed. Some of the exaggerated mathematical calculations of Borelli himself are worth noting. Each heart-beat, as he calculated it, overcomes a resistance equal to one hundred and eighty thousand pounds;–the modern physiologist estimates its force at from five to nine ounces!


But while the Continent was struggling with these illusive “systems,” and dabbling in mystic theories that were to scarcely outlive the men who conceived

them, there appeared in England–the “land of common-sense,” as a German scientist has called it–“a cool, clear, and unprejudiced spirit,” who in the golden age of systems declined “to be like the man who builds the chambers of the upper story of his house before he had laid securely the foundation walls.”[1] This man was Thomas Sydenham (1624-1689), who, while the great Harvey was serving the king as surgeon, was fighting as a captain in the parliamentary army. Sydenham took for his guide the teachings of Hippocrates, modified to suit the advances that had been made in scientific knowledge since the days of the great Greek, and established, as a standard, observation and experience. He cared little for theory unless confirmed by practice, but took the Hippocratic view that nature cured diseases, assisted by the physician. He gave due credit, however, to the importance of the part played by the assistant. As he saw it, medicine could be advanced in three ways: (1) “By accurate descriptions or natural histories of diseases; (2) by establishing a fixed principle or method of treatment, founded upon experience; (3) by searching for specific remedies, which he believes must exist in considerable numbers, though he admits that the only one yet discovered is Peruvian bark.”[2] As it happened, another equally specific remedy, mercury, when used in certain diseases, was already known to him, but he evidently did not recognize it as such.

The influence on future medicine of Sydenham’s teachings was most pronounced, due mostly to his teaching of careful observation. To most physicians, however, he is now remembered chiefly for his introduction of the use of laudanum, still considered one of the most valuable remedies of modern pharmacopoeias. The German gives the honor of introducing this preparation to Paracelsus, but the English-speaking world will always believe that the credit should be given to Sydenham.


We saw that in the old Greek days there was no sharp line of demarcation between the field of the philosopher and that of the scientist. In the Hellenistic epoch, however, knowledge became more specialized, and our recent chapters have shown us scientific investigators whose efforts were far enough removed from the intangibilities of the philosopher. It must not be overlooked, however, that even in the present epoch there were men whose intellectual efforts were primarily directed towards the subtleties of philosophy, yet who had also a penchant for strictly scientific imaginings, if not indeed for practical scientific experiments. At least three of these men were of sufficient importance in the history of the development of science to demand more than passing notice. These three are the Englishman Francis Bacon (1561-1626), the Frenchman Rene Descartes (1596-1650); and the German Gottfried Leibnitz (1646-1716). Bacon, as the earliest path-breaker, showed the way, theoretically at least, in which the sciences should be studied; Descartes, pursuing the methods pointed out by Bacon, carried the same line of abstract reason into practice as well; while Leibnitz, coming some years later, and having the advantage of the wisdom of his two great predecessors, was naturally influenced by both in his views of abstract scientific principles.

Bacon’s career as a statesman and his faults and misfortunes as a man do not concern us here. Our interest in him begins with his entrance into Trinity College, Cambridge, where he took up the study of all the sciences taught there at that time. During the three years he became more and more convinced that science was not being studied in a profitable manner, until at last, at the end of his college course, he made ready to renounce the old Aristotelian methods of study and advance his theory of inductive study. For although he was a great admirer of Aristotle’s work, he became convinced that his methods of approaching study were entirely wrong.

“The opinion of Aristotle,” he says, in his De Argumentum Scientiarum, “seemeth to me a negligent opinion, that of those things which exist by nature nothing can be changed by custom; using for example, that if a stone be thrown ten thousand times up it will not learn to ascend; and that by often seeing or hearing we do not learn to see or hear better. For though this principle be true in things wherein nature is peremptory (the reason whereof we cannot now stand to discuss), yet it is otherwise in things wherein nature admitteth a latitude. For he might see that a straight glove will come more easily on with use; and that a wand will by use bend otherwise than it grew; and that by use of the voice we speak louder and stronger; and that by use of enduring heat or cold we endure it the better, and the like; which latter sort have a nearer resemblance unto that subject of manners he handleth than those instances which he allegeth.”[1]

These were his opinions, formed while a young man in college, repeated at intervals through his maturer years, and reiterated and emphasized in his old age. Masses of facts were to be obtained by observing nature at first hand, and from such accumulations of facts deductions were to be made. In short, reasoning was to be from the specific to the general, and not vice versa.

It was by his teachings alone that Bacon thus contributed to the foundation of modern science; and, while he was constantly thinking and writing on scientific subjects, he contributed little in the way of actual discoveries. “I only sound the clarion,” he said, “but I enter not the battle.”

The case of Descartes, however, is different. He both sounded the clarion and entered into the fight. He himself freely acknowledges his debt to Bacon for his teachings of inductive methods of study, but modern criticism places his work on the same plane as that of the great Englishman. “If you lay hold of any characteristic product of modern ways of thinking,” says Huxley, “either in the region of philosophy or in that of science, you find the spirit of that thought, if not its form, has been present in the mind of the great Frenchman.”[2]

Descartes, the son of a noble family of France, was educated by Jesuit teachers. Like Bacon, he very early conceived the idea that the methods of teaching and studying science were wrong, but be pondered the matter well into middle life before putting into writing his ideas of philosophy and science. Then, in his Discourse Touching the Method of Using One’s Reason Rightly and of Seeking Scientific Truth, he pointed out the way of seeking after truth. His central idea in this was to emphasize the importance of DOUBT, and avoidance of accepting as truth anything that does not admit of absolute and unqualified proof. In reaching these conclusions he had before him the striking examples of scientific deductions by Galileo, and more recently the discovery of the circulation of the blood by Harvey. This last came as a revelation to scientists, reducing this seemingly occult process, as it did, to the field of mechanical phenomena. The same mechanical laws that governed the heavenly bodies, as shown by Galileo, governed the action of the human heart, and, for aught any one knew, every part of the body, and even the mind itself.

Having once conceived this idea, Descartes began a series of dissections and experiments upon the lower animals, to find, if possible, further proof of this general law. To him the human body was simply a machine, a complicated mechanism, whose functions were controlled just as any other piece of machinery. He compared the human body to complicated machinery run by water-falls and complicated pipes. “The nerves of the machine which I am describing,” he says, “may very well be compared to the pipes of these waterworks; its muscles and its tendons to the other various engines and springs which seem to move them; its animal spirits to the water which impels them, of which the heart is the fountain; while the cavities of the brain are the central office. Moreover, respiration and other such actions as are natural and usual in the body, and which depend on the course of the spirits, are like the movements of a clock, or a mill, which may be kept up by the ordinary flow of water.”[3]

In such passages as these Descartes anticipates the ideas of physiology of the present time. He believed that the functions are performed by the various organs of the bodies of animals and men as a mechanism, to which in man was added the soul. This soul he located in the pineal gland, a degenerate and presumably functionless little organ in the brain. For years Descartes’s idea of the function of this gland was held by many physiologists, and it was only the introduction of modern high-power microscopy that reduced this also to a mere mechanism, and showed that it is apparently the remains of a Cyclopean eye once common to man’s remote ancestors.

Descartes was the originator of a theory of the movements of the universe by a mechanical process–the Cartesian theory of vortices–which for several decades after its promulgation reigned supreme in science. It is the ingenuity of this theory, not the truth of its assertions, that still excites admiration, for it has long since been supplanted. It was certainly the best hitherto advanced–the best “that the observations of the age admitted,” according to D’Alembert.

According to this theory the infinite universe is full of matter, there being no such thing as a vacuum. Matter, as Descartes believed, is uniform in character throughout the entire universe, and since motion cannot take place in any part of a space completely filled, without simultaneous movement in all other parts, there are constant more or less circular movements, vortices, or whirlpools of particles, varying, of course, in size and velocity. As a result of this circular movement the particles of matter tend to become globular from contact with one another. Two species of matter are thus formed, one larger and globular, which continue their circular motion with a constant tendency to fly from the centre of the axis of rotation, the other composed of the clippings resulting from the grinding process. These smaller “filings” from the main bodies, becoming smaller and smaller, gradually lose their velocity and accumulate in the centre of the vortex. This collection of the smaller matter in the centre of the vortex constitutes the sun or star, while the spherical particles propelled in straight lines from the centre towards the circumference of the vortex produce the phenomenon of light radiating from the central star. Thus this matter becomes the atmosphere revolving around the accumulation at the centre. But the small particles being constantly worn away from the revolving spherical particles in the vortex, become entangled in their passage, and when they reach the edge of the inner strata of solar dust they settle upon it and form what we call sun-spots. These are constantly dissolved and reformed, until sometimes they form a crust round the central nucleus.

As the expansive force of the star diminishes in the course of time, it is encroached upon by neighboring vortices. If the part of the encroaching star be of a less velocity than the star which it has swept up, it will presently lose its hold, and the smaller star pass out of range, becoming a comet. But if the velocity of the vortex into which the incrusted star settles be equivalent to that of the surrounded vortex, it will hold it as a captive, still revolving and “wrapt in its own firmament.” Thus the several planets of our solar system have been captured and held by the sun-vortex, as have the moon and other satellites.

But although these new theories at first created great enthusiasm among all classes of philosophers and scientists, they soon came under the ban of the Church. While no actual harm came to Descartes himself, his writings were condemned by the Catholic and Protestant churches alike. The spirit of philosophical inquiry he had engendered, however, lived on, and is largely responsible for modern philosophy.

In many ways the life and works of Leibnitz remind us of Bacon rather than Descartes. His life was spent in filling high political positions, and his philosophical and scientific writings were by-paths of his fertile mind. He was a theoretical rather than a practical scientist, his contributions to science being in the nature of philosophical reasonings rather than practical demonstrations. Had he been able to withdraw from public life and devote himself to science alone, as Descartes did, he would undoubtedly have proved himself equally great as a practical worker. But during the time of his greatest activity in philosophical fields, between the years 1690 and 1716, he was all the time performing extraordinary active duties in entirely foreign fields. His work may be regarded, perhaps, as doing for Germany in particular what Bacon’s did for England and the rest of the world in general.

Only a comparatively small part of his philosophical writings concern us here. According to his theory of the ultimate elements of the universe, the entire universe is composed of individual centres, or monads. To these monads he ascribed numberless qualities by which every phase of nature may be accounted. They were supposed by him to be percipient, self-acting beings, not under arbitrary control of the deity, and yet God himself was the original monad from which all the rest are generated. With this conception as a basis, Leibnitz deduced his doctrine of pre-established harmony, whereby the numerous independent substances composing the world are made to form one universe. He believed that by virtue of an inward energy monads develop themselves spontaneously, each being independent of every other. In short, each monad is a kind of deity in itself–a microcosm representing all the great features of the macrocosm.

It would be impossible clearly to estimate the precise value of the stimulative influence of these philosophers upon the scientific thought of their time. There was one way, however, in which their influence was made very tangible–namely, in the incentive they gave to the foundation of scientific societies.


At the present time, when the elements of time and distance are practically eliminated in the propagation of news, and when cheap printing has minimized the difficulties of publishing scientific discoveries, it is difficult to understand the isolated position of the scientific investigation of the ages that preceded steam and electricity. Shut off from the world and completely out of touch with fellow-laborers perhaps only a few miles away, the investigators were naturally seriously handicapped; and inventions and discoveries were not made with the same rapidity that they would undoubtedly have been had the same men been receiving daily, weekly, or monthly communications from fellow-laborers all over the world, as they do to-day. Neither did they have the advantage of public or semi-public laboratories, where they were brought into contact with other men, from whom to gather fresh trains of thought and receive the stimulus of their successes or failures. In the natural course of events, however, neighbors who were interested in somewhat similar pursuits, not of the character of the rivalry of trade or commerce, would meet more or less frequently and discuss their progress. The mutual advantages of such intercourse would be at once appreciated; and it would be but a short step from the casual meeting of two neighborly scientists to the establishment of “societies,” meeting at fixed times, and composed of members living within reasonable travelling distance. There would, perhaps, be the weekly or monthly meetings of men in a limited area; and as the natural outgrowth of these little local societies, with frequent meetings, would come the formation of larger societies, meeting less often, where members travelled a considerable distance to attend. And, finally, with increased facilities for communication and travel, the great international societies of to-day would be produced–the natural outcome of the neighborly meetings of the primitive mediaeval investigators.

In Italy, at about the time of Galileo, several small societies were formed. One of the most important of these was the Lyncean Society, founded about the year 1611, Galileo himself being a member. This society was succeeded by the Accademia del Cimento, at Florence, in 1657, which for a time flourished, with such a famous scientist as Torricelli as one of its members.

In England an impetus seems to have been given by Sir Francis Bacon’s writings in criticism and censure of the systern of teaching in colleges. It is supposed that his suggestions as to what should be the aims of a scientific society led eventually to the establishment of the Royal Society. He pointed out how little had really been accomplished by the existing institutions of learning in advancing science, and asserted that little good could ever come from them while their methods of teaching remained unchanged. He contended that the system which made the lectures and exercises of such a nature that no deviation from the established routine could be thought of was pernicious. But he showed that if any teacher had the temerity to turn from the traditional paths, the daring pioneer was likely to find insurmountable obstacles placed in the way of his advancement. The studies were “imprisoned” within the limits of a certain set of authors, and originality in thought or teaching was to be neither contemplated nor tolerated.

The words of Bacon, given in strong and unsparing terms of censure and condemnation, but nevertheless with perfect justification, soon bore fruit. As early as the year 1645 a small company of scientists had been in the habit of meeting at some place in London to discuss philosophical and scientific subjects for mental advancement. In 1648, owing to the political disturbances of the time, some of the members of these meetings removed to Oxford, among them Boyle, Wallis, and Wren, where the meetings were continued, as were also the meetings of those left in London. In 1662, however, when the political situation bad become more settled, these two bodies of men were united under a charter from Charles II., and Bacon’s ideas were practically expressed in that learned body, the Royal Society of London. And it matters little that in some respects Bacon’s views were not followed in the practical workings of the society, or that the division of labor in the early stages was somewhat different than at present. The aim of the society has always been one for the advancement of learning; and if Bacon himself could look over its records, he would surely have little fault to find with the aid it has given in carrying out his ideas for the promulgation of useful knowledge.

Ten years after the charter was granted to the Royal Society of London, Lord Bacon’s words took practical effect in Germany, with the result that the Academia Naturae Curiosorum was founded, under the leadership of Professor J. C. Sturm. The early labors of this society were devoted to a repetition of the most notable experiments of the time, and the work of the embryo society was published in two volumes, in 1672 and 1685 respectively, which were practically text-books of the physics of the period. It was not until 1700 that Frederick I. founded the Royal Academy of Sciences at Berlin, after the elaborate plan of Leibnitz, who was himself the first president.

Perhaps the nearest realization of Bacon’s ideal, however, is in the Royal Academy of Sciences at Paris, which was founded in 1666 under the administration of Colbert, during the reign of Louis XIV. This institution not only recognized independent members, but had besides twenty pensionnaires who received salaries from the government. In this way a select body of scientists were enabled to pursue their investigations without being obliged to “give thought to the morrow” for their sustenance. In return they were to furnish the meetings with scientific memoirs, and once a year give an account of the work they were engaged upon. Thus a certain number of the brightest minds were encouraged to devote their entire time to scientific research, “delivered alike from the temptations of wealth or the embarrassments of poverty.” That such a plan works well is amply attested by the results emanating from the French academy. Pensionnaires in various branches of science, however, either paid by the state or by learned societies, are no longer confined to France.

Among the other early scientific societies was the Imperial Academy of Sciences at St. Petersburg, projected by Peter the Great, and established by his widow, Catharine I., in 1725; and also the Royal Swedish Academy, incorporated in 1781, and counting among its early members such men as the celebrated Linnaeus. But after the first impulse had resulted in a few learned societies, their manifest advantage was so evident that additional numbers increased rapidly, until at present almost every branch of every science is represented by more or less important bodies; and these are, individually and collectively, adding to knowledge and stimulating interest in the many fields of science, thus vindicating Lord Bacon’s asseverations that knowledge could be satisfactorily promulgated in this manner.


We have now to witness the diversified efforts of a company of men who, working for the most part independently, greatly added to the data of the physical sciences–such men as Boyle, Huygens, Von Gericke, and Hooke. It will be found that the studies of these men covered the whole field of physical sciences as then understood–the field of so-called natural philosophy. We shall best treat these successors of Galileo and precursors of Newton somewhat biographically, pointing out the correspondences and differences between their various accomplishments as we proceed. It will be noted in due course that the work of some of them was anticipatory of great achievements of a later century.

ROBERT BOYLE (1627-1691)

Some of Robert Boyle’s views as to the possible structure of atmospheric air will be considered a little farther on in this chapter, but for the moment we will take up the consideration of some of his experiments upon that as well as other gases. Boyle was always much interested in alchemy, and carried on extensive experiments in attempting to accomplish the transmutation of metals; but he did not confine himself to these experiments, devoting himself to researches in all the fields of natural philosophy. He was associated at Oxford with a company of scientists, including Wallis and Wren, who held meetings and made experiments together, these gatherings being the beginning, as mentioned a moment ago, of what finally became the Royal Society. It was during this residence at Oxford that many of his valuable researches upon air were made, and during this time be invented his air-pump, now exhibited in the Royal Society rooms at Burlington House.[1]

His experiments to prove the atmospheric pressure are most interesting and conclusive. “Having three small, round glass bubbles, blown at the flame of a lamp, about the size of hazel-nuts,” he says, “each of them with a short, slender stem, by means whereof they were so exactly poised in water that a very small change of weight would make them either emerge or sink; at a time when the atmosphere was of convenient weight, I put them into a wide-mouthed glass of common water, and leaving them in a quiet place, where they were frequently in my eye, I observed that sometimes they would be at the top of the water, and remain there for several days, or perhaps weeks, together, and sometimes fall to the bottom, and after having continued there for some time rise again. And sometimes they would rise or fall as the air was hot or cold.”[2]

It was in the course of these experiments that the observations made by Boyle led to the invention of his “statical barometer,” the mercurial barometer having been invented, as we have seen, by Torricelli, in 1643. In describing this invention he says: “Making choice of a large, thin, and light glass bubble, blown at the flame of a lamp, I counterpoised it with a metallic weight, in a pair of scales that were suspended in a frame, that would turn with the thirtieth part of a grain. Both the frame and the balance were then placed near a good barometer, whence I might learn the present weight of the atmosphere; when, though the scales were unable to show all the variations that appeared in the mercurial barometer, yet they gave notice of those that altered the height of the mercury half a quarter of an inch.”[3] A fairly sensitive barometer, after all. This statical barometer suggested several useful applications to the fertile imagination of its inventor, among others the measuring of mountain-peaks, as with the mercurial barometer, the rarefication of the air at the top giving a definite ratio to the more condensed air in the valley.

Another of his experiments was made to discover the atmospheric pressure to the square inch. After considerable difficulty he determined that the relative weight of a cubic inch of water and mercury was about one to fourteen, and computing from other known weights he determined that “when a column of quicksilver thirty inches high is sustained in the barometer, as it frequently happens, a column of air that presses upon an inch square near the surface of the earth must weigh about fifteen avoirdupois pounds.”[4] As the pressure of air at the sea-level is now estimated at 14.7304 pounds to the square inch, it will be seen that Boyle’s calculation was not far wrong.

From his numerous experiments upon the air, Boyle was led to believe that there were many “latent qualities” due to substances contained in it that science had as yet been unable to fathom, believing that there is “not a more heterogeneous body in the world.” He believed that contagious diseases were carried by the air, and suggested that eruptions of the earth, such as those made by earthquakes, might send up “venomous exhalations” that produced diseases. He suggested also that the air might play an important part in some processes of calcination, which, as we shall see, was proved to be true by Lavoisier late in the eighteenth century. Boyle’s notions of the exact chemical action in these phenomena were of course vague and indefinite, but he had observed that some part was played by the air, and he was right in supposing that the air “may have a great share in varying the salts obtainable from calcined vitriol.”[5]

Although he was himself such a painstaking observer of facts, he had the fault of his age of placing too much faith in hear-say evidence of untrained observers. Thus, from the numerous stories he heard concerning the growth of metals in previously exhausted mines, he believed that the air was responsible for producing this growth–in which he undoubtedly believed. The story of a tin-miner that, in his own time, after a lapse of only twenty-five years, a heap, of earth previously exhausted of its ore became again even more richly impregnated than before by lying exposed to the air, seems to have been believed by the philosopher.

As Boyle was an alchemist, and undoubtedly believed in the alchemic theory that metals have “spirits” and various other qualities that do not exist, it is not surprising that he was credulous in the matter of beliefs concerning peculiar phenomena exhibited by them. Furthermore, he undoubtedly fell into the error common to “specialists,” or persons working for long periods of time on one subject–the error of over-enthusiasm in his subject. He had discovered so many remarkable qualities in the air that it is not surprising to find that he attributed to it many more that he could not demonstrate.

Boyle’s work upon colors, although probably of less importance than his experiments and deductions upon air, show that he was in the van as far as the science of his day was concerned. As he points out, the schools of his time generally taught that “color is a penetrating quality, reaching to the innermost part of the substance,” and, as an example of this, sealing-wax was cited, which could be broken into minute bits, each particle retaining the same color as its fellows or the original mass. To refute this theory, and to show instances to the contrary, Boyle, among other things, shows that various colors–blue, red, yellow–may be produced upon tempered steel, and yet the metal within “a hair’s-breadth of its surface” have none of these colors. Therefore, he was led to believe that color, in opaque bodies at least, is superficial.

“But before we descend to a more particular consideration of our subject,” he says, ” ’tis proper to observe that colors may be regarded either as a quality residing in bodies to modify light after a particular manner, or else as light itself so modified as to strike upon the organs of sight, and cause the sensation we call color; and that this latter is the more proper acceptation of the word color will appear hereafter. And indeed it is the light itself, which after a certain manner, either mixed with shades or other-wise, strikes our eyes and immediately produces that motion in the organ which gives us the color of an object.”[6]

In examining smooth and rough surfaces to determine the cause of their color, he made use of the microscope, and pointed out the very obvious example of the difference in color of a rough and a polished piece of the same block of stone. He used some striking illustrations of the effect of light and the position of the eye upon colors. “Thus the color of plush or velvet will appear various if you stroke part of it one way and part another, the posture of the particular threads in regard to the light, or the eye, being thereby varied. And ’tis observable that in a field of ripe corn, blown upon by the wind, there will appear waves of a color different from that of the rest of the corn, because the wind, by depressing some of the ears more than others, causes one to reflect more light from the lateral and strawy parts than another.”[7] His work upon color, however, as upon light, was entirely overshadowed by the work of his great fellow-countryman Newton.

Boyle’s work on electricity was a continuation of Gilbert’s, to which he added several new facts. He added several substances to Gilbert’s list of “electrics,” experimented on smooth and rough surfaces in exciting of electricity, and made the important discovery that amber retained its attractive virtue after the friction that excited it bad ceased. “For the attrition having caused an intestine motion in its parts,” he says, “the heat thereby excited ought not to cease as soon as ever the rubbing is over, but to continue capable of emitting effluvia for some time afterwards, longer or shorter according to the goodness of the electric and the degree of the commotion made; all which, joined together, may sometimes make the effect considerable; and by this means, on a warm day, I, with a certain body not bigger than a pea, but very vigorously attractive, moved a steel needle, freely poised, about three minutes after I had left off rubbing it.”[8]


Working contemporaneously with Boyle, and a man whose name is usually associated with his as the propounder of the law of density of gases, was Edme Mariotte (died 1684), a native of Burgundy. Mariotte demonstrated that but for the resistance of the atmosphere, all bodies, whether light or heavy, dense or thin, would fall with equal rapidity, and he proved this by the well-known “guinea-and-feather” experiment. Having exhausted the air from a long glass tube in which a guinea piece and a feather had been placed, he showed that in the vacuum thus formed they fell with equal rapidity as often as the tube was reversed. From his various experiments as to the pressure of the atmosphere he deduced the law that the density and elasticity of the atmosphere are precisely proportional to the compressing force (the law of Boyle and Mariotte). He also ascertained that air existed in a state of mechanical mixture with liquids, “existing between their particles in a state of condensation.” He made many other experiments, especially on the collision of bodies, but his most important work was upon the atmosphere.

But meanwhile another contemporary of Boyle and Mariotte was interesting himself in the study of the atmosphere, and had made a wonderful invention and a most striking demonstration. This was Otto von Guericke (1602-1686), Burgomaster of Magdeburg, and councillor to his “most serene and potent Highness” the elector of that place. When not engrossed with the duties of public office, he devoted his time to the study of the sciences, particularly pneumatics and electricity, both then in their infancy. The discoveries of Galileo, Pascal, and Torricelli incited him to solve the problem of the creation of a vacuum–a desideratum since before the days of Aristotle. His first experiments were with a wooden pump and a barrel of water, but he soon found that with such porous material as wood a vacuum could not be created or maintained. He therefore made use of a globe of copper, with pump and stop-cock; and with this he was able to pump out air almost as easily as water. Thus, in 1650, the air-pump was invented. Continuing his experiments upon vacuums and atmospheric pressure with his newly discovered pump, he made some startling discoveries as to the enormous pressure exerted by the air.

It was not his intention, however, to demonstrate his newly acquired knowledge by words or theories alone, nor by mere laboratory experiments; but he chose instead an open field, to which were invited Emperor Ferdinand III., and all the princes of the Diet at Ratisbon. When they were assembled he produced two hollow brass hemispheres about two feet in diameter, and placing their exactly fitting surfaces together, proceeded to pump out the air from their hollow interior, thus causing them to stick together firmly in a most remarkable way, apparently without anything holding them. This of itself was strange enough; but now the worthy burgomaster produced teams of horses, and harnessing them to either side of the hemispheres, attempted to pull the adhering brasses apart. Five, ten, fifteen teams–thirty horses, in all–were attached; but pull and tug as they would they could not separate the firmly clasped hemispheres. The enormous pressure of the atmosphere had been most strikingly demonstrated.

But it is one thing to demonstrate, another to convince; and many of the good people of Magdeburg shook their heads over this “devil’s contrivance,” and predicted that Heaven would punish the Herr Burgomaster, as indeed it had once by striking his house with lightning and injuring some of his infernal contrivances. They predicted his future punishment, but they did not molest him, for to his fellow-citizens, who talked and laughed, drank and smoked with him, and knew him for the honest citizen that he was, he did not seem bewitched at all. And so he lived and worked and added other facts to science, and his brass hemispheres were not destroyed by fanatical Inquisitors, but are still preserved in the royal library at Berlin.

In his experiments with his air-pump he discovered many things regarding the action of gases, among others, that animals cannot live in a vacuum. He invented the anemoscope and the air-balance, and being thus enabled to weight the air and note the changes that preceded storms and calms, he was able still further to dumfound his wondering fellow-Magde-burgers by more or less accurate predictions about the weather.

Von Guericke did not accept Gilbert’s theory that the earth was a great magnet, but in his experiments along lines similar to those pursued by Gilbert, he not only invented the first electrical machine, but discovered electrical attraction and repulsion. The electrical machine which he invented consisted of a sphere of sulphur mounted on an iron axis to imitate the rotation of the earth, and which, when rubbed, manifested electrical reactions. When this globe was revolved and stroked with the dry hand it was found that it attached to it “all sorts of little fragments, like