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Autobiography and Selected Essays by Thomas Henry Huxley

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rock builders.

What has been said of the animal world is no less true of plants.
Imbedded in the protoplasm at the broad, or attached, end of the
nettle hair, there lies a spheroidal nucleus. Careful examination
further proves that the whole substance of the nettle is made up of
a repetition of such masses of nucleated protoplasm, each contained
in a wooden case, which is modified in form, sometimes into a woody
fibre, sometimes into a duct or spiral vessel, sometimes into a
pollen grain, or an ovule. Traced back to its earliest state, the
nettle arises as the man does, in a particle of nucleated
protoplasm. And in the lowest plants, as in the lowest animals, a
single mass of such protoplasm may constitute the whole plant, or
the protoplasm may exist without a nucleus.

Under these circumstances it may well be asked, how is one mass of
non-nucleated protoplasm to be distinguished from another? why call
one "plant" and the other "animal"?

The only reply is that, so far as form is concerned, plants and
animals are not separable, and that, in many cases, it is a mere
matter of convention whether we call a given organism an animal or
a plant. There is a living body called Aethalium septicum, which
appears upon decaying vegetable substances, and, in one of its
forms, is common upon the surfaces of tan-pits. In this condition
it is, to all intents and purposes, a fungus, and formerly was
always regarded as such; but the remarkable investigations of De
Bary [99] have shown that, in another condition, the Aethalium is an
actively locomotive creature, and takes in solid matters, upon
which, apparently, it feeds, thus exhibiting the most characteristic
feature of animality. Is this a plant; or is it an animal?
Is it both; or is it neither? Some decide in favour of the last
supposition, and establish an intermediate kingdom, a sort
of biological No Man's Land [100] for all these questionable forms.
But, as it is admittedly impossible to draw any distinct boundary line
between this no man's land and the vegetable world on the one hand,
or the animal, on the other, it appears to me that this proceeding
merely doubles the difficulty which, before, was single.

Protoplasm, simple or nucleated, is the formal basis of all life.
It is the clay of the potter: which, bake it and paint it as he
will, remains clay, separated by artifice, and not by nature, from
the commonest brick or sun-dried clod.

Thus it becomes clear that all living powers are cognate, and
that all living forms are fundamentally of one character. The
researches of the chemist have revealed a no less striking
uniformity of material composition in living matter.

In perfect strictness, it is true that chemical investigation can
tell us little or nothing, directly, of the composition of living
matter, inasmuch as such matter must needs die in the act of
analysis,--and upon this very obvious ground, objections, which I
confess seem to me to be somewhat frivolous, have been raised to
the drawing of any conclusions whatever respecting the composition
of actually living matter, from that of the dead matter of life,
which alone is accessible to us. But objectors of this class do
not seem to reflect that it is also, in strictness, true that we
know nothing about the composition of any body whatever, as it is.
The statement that a crystal of calc-spar consists of carbonate of
lime, is quite true, if we only mean that, by appropriate
processes, it may be resolved into carbonic acid and quicklime. If
you pass the same carbonic acid over the very quicklime thus
obtained, you will obtain carbonate of lime again; but it will not
be calc-spar, nor anything like it. Can it, therefore, be said
that chemical analysis teaches nothing about the chemical
composition of calc-spar? Such a statement would be absurd; but it
is hardly more so than the talk one occasionally hears about the
uselessness of applying the results of chemical analysis to the
living bodies which have yielded them.

One fact, at any rate, is out of reach of such refinements, and
this is, that all the forms of protoplasm which have yet been
examined contain the four elements, carbon, hydrogen, oxygen, and
nitrogen, in very complex union, and that they behave similarly
towards several reagents. To this complex combination, the nature
of which has never been determined with exactness, the name of
Protein has been applied. And if we use this term with such
caution as may properly arise out of our comparative ignorance of
the things for which it stands, it may be truly said, that all
protoplasm is proteinaceous, or, as the white, or albumen, of an
egg is one of the commonest examples of a nearly pure proteine
matter, we may say that all living matter is more or less

Perhaps it would not yet be safe to say that all forms of
protoplasm are affected by the direct action of electric shocks;
and yet the number of cases in which the contraction of protoplasm
is shown to be affected by this agency increases every day.

Nor can it be affirmed with perfect confidence, that all forms of
protoplasm are liable to undergo that peculiar coagulation at a
temperature of 40-50 degrees centigrade, which has been called
"heat-stiffening," though Kuhne's [101] beautiful researches have
proved this occurrence to take place in so many and such diverse
living beings, that it is hardly rash to expect that the law holds
good for all.

Enough has, perhaps, been said to prove the existence of a general
uniformity in the character of the protoplasm, or physical basis,
of life, in whatever group of living beings it may be studied. But
it will be understood that this general uniformity by no means
excludes any amount of special modifications of the fundamental
substance. The mineral, carbonate of lime, assumes an immense
diversity of characters, though no one doubts that, under all these
Protean changes, it is one and the same thing.

And now, what is the ultimate fate, and what the origin, of the
matter of life?

Is it, as some of the older naturalists supposed, diffused
throughout the universe in molecules, which are indestructible and
unchangeable in themselves; but, in endless transmigration, unite
in innumerable permutations, into the diversified forms of life we
know? Or, is the matter of life composed of ordinary matter,
differing from it only in the manner in which its atoms are
aggregated? Is it built up of ordinary matter, and again resolved
into ordinary matter when its work is done?

Modern science does not hesitate a moment between these
alternatives. Physiology writes over the portals of life--

"Debemur morti nos nostraque,"[102]

with a profounder meaning than the Roman poet attached to that
melancholy line. Under whatever disguise it takes refuge, whether
fungus or oak, worm or man, the living protoplasm not only
ultimately dies and is resolved into its mineral and lifeless
constituents, but is always dying, and, strange as the paradox may
sound, could not live unless it died.

In the wonderful story of the Peau de Chagrin,[103] the hero becomes
possessed of a magical wild ass' skin, which yields him the means
of gratifying all his wishes. But its surface represents the
duration of the proprietor's life; and for every satisfied desire
the skin shrinks in proportion to the intensity of fruition, until
at length life and the last handbreadth of the peau de chagrin,
disappear with the gratification of a last wish.

Balzac's [104] studies had led him over a wide range of thought and
speculation, and his shadowing forth of physiological truth in this
strange story may have been intentional. At any rate, the matter
of life is a veritable peau de chagrin, and for every vital act it
is somewhat the smaller. All work implies waste, and the work of
life results, directly or indirectly, in the waste of protoplasm.

Every word uttered by a speaker costs him some physical loss; and,
in the strictest sense, he burns that others may have light--so
much eloquence, so much of his body resolved into carbonic acid,
water, and urea. It is clear that this process of expenditure
cannot go on for ever. But, happily, the protoplasmic peau de
chagrin differs from Balzac's in its capacity of being repaired,
and brought back to its full size, after every exertion.

For example, this present lecture, whatever its intellectual worth
to you, has a certain physical value to me, which is, conceivably,
expressible by the number of grains of protoplasm and other bodily
substance wasted in maintaining my vital processes during its
delivery. My peau de chagrin will be distinctly smaller at the end
of the discourse than it was at the beginning. By and by, I shall
probably have recourse to the substance commonly called mutton, for
the purpose of stretching it back to its original size. Now this
mutton was once the living protoplasm, more or less modified, of
another animal--a sheep. As I shall eat it, it is the same matter
altered, not only by death, but by exposure to sundry artificial
operations in the process of cooking.

But these changes, whatever be their extent, have not rendered it
incompetent to resume its old functions as matter of life. A
singular inward laboratory, which I possess, will dissolve a
certain portion of the modified protoplasm; the solution so formed
will pass into my veins; and the subtle influences to which it will
then be subjected will convert the dead protoplasm into living
protoplasm, and transubstantiate sheep into man.

Nor is this all. If digestion were a thing to be trifled with, I
might sup upon lobster, and the matter of life of the crustacean
would undergo the same wonderful metamorphosis into humanity. And
were I to return to my own place by sea, and undergo shipwreck, the
crustacean might, and probably would, return the compliment, and
demonstrate our common nature by turning my protoplasm into living
lobster. Or, if nothing better were to be had, I might supply my
wants with mere bread, and I should find the protoplasm of the
wheat-plant to be convertible into man, with no more trouble than
that of the sheep, and with far less, I fancy, than that of the

Hence it appears to be a matter of no great moment what animal, or
what plant, I lay under contribution for protoplasm, and the fact
speaks volumes for the general identity of that substance in all
living beings. I share this catholicity of assimilation with other
animals, all of which, so far as we know, could thrive equally well
on the protoplasm of any of their fellows, or of any plant; but
here the assimilative powers of the animal world cease. A solution
of smelling-salts in water, with an infinitesimal proportion of
some other saline matters, contains all the elementary bodies which
enter into the composition of protoplasm; but, as I need hardly
say, a hogshead of that fluid would not keep a hungry man from
starving, nor would it save any animal whatever from a like fate.
An animal cannot make protoplasm, but must take it ready-made from
some other animal, or some plant--the animal's highest feat of
constructive chemistry being to convert dead protoplasm into that
living matter of life which is appropriate to itself.

Therefore, in seeking for the origin of protoplasm, we must
eventually turn to the vegetable world. A fluid containing
carbonic acid, water, and nitrogenous salts, which offers such a
Barmecide feast [105] to the animal, is a table richly spread to
multitudes of plants; and, with a due supply of only such
materials, many a plant will not only maintain itself in vigour,
but grow and multiply until it has increased a million-fold, or a
million million-fold, the quantity of protoplasm which it
originally possessed; in this way building up the matter of life,
to an indefinite extent, from the common matter of the universe.

Thus, the animal can only raise the complex substance of dead
protoplasm to the higher power, as one may say, of living
protoplasm; while the plant can raise the less complex substances--
carbonic acid, water, and nitrogenous salts--to the same stage of
living protoplasm, if not to the same level. But the plant also
has its limitations. Some of the fungi, for example, appear to
need higher compounds to start with; and no known plant can live
upon the uncompounded elements of protoplasm. A plant supplied
with pure carbon, hydrogen, oxygen, and nitrogen, phosphorus,
sulphur, and the like, would as infallibly die as the animal in his
bath of smelling-salts, though it would be surrounded by all the
constituents of protoplasm. Nor, indeed, need the process of
simplification of vegetable food be carried so far as this, in
order to arrive at the limit of the plant's thaumaturgy. Let
water, carbonic acid, and all the other needful constituents be
supplied except nitrogenous salts, and an ordinary plant will still
be unable to manufacture protoplasm.

Thus the matter of life, so far as we know it (and we have no right
to speculate on any other), breaks up, in consequence of that
continual death which is the condition of its manifesting vitality,
into carbonic acid, water, and nitrogenous compounds, which
certainly possess no properties but those of ordinary matter. And
out of these same forms of ordinary matter, and from none which are
simpler, the vegetable world builds up all the protoplasm which
keeps the animal world a-going. Plants are the accumulators of the
power which animals distribute and disperse.

But it will be observed, that the existence of the matter of life
depends on the pre-existence of certain compounds; namely, carbonic
acid, water, and certain nitrogenous bodies. Withdraw any one of
these three from the world, and all vital phaenomena come to an
end. They are as necessary to the protoplasm of the plant, as the
protoplasm of the plant is to that of the animal. Carbon,
hydrogen, oxygen, and nitrogen are all lifeless bodies. Of these,
carbon and oxygen unite in certain proportions and under certain
conditions, to give rise to carbonic acid; hydrogen and oxygen
produce water; nitrogen and other elements give rise to nitrogenous
salts. These new compounds, like the elementary bodies of which
they are composed, are lifeless. But when they are brought
together, under certain conditions, they give rise to the still
more complex body, protoplasm, and this protoplasm exhibits the
phaenomena of life.

I see no break in this series of steps in molecular complication,
and I am unable to understand why the language which is applicable
to any one term of the series may not be used to any of the others.
We think fit to call different kinds of matter carbon, oxygen,
hydrogen, and nitrogen, and to speak of the various powers and
activities of these substances as the properties of the matter of
which they are composed.

When hydrogen and oxygen are mixed in a certain proportion, and an
electric spark is passed through them, they disappear, and a
quantity of water, equal in weight to the sum of their weights,
appears in their place. There is not the slightest parity between
the passive and active powers of the water and those of the oxygen
and hydrogen which have given rise to it. At 32 degrees
Fahrenheit, and far below that temperature, oxygen and hydrogen are
elastic gaseous bodies, whose particles tend to rush away from one
another with great force. Water, at the same temperature, is a
strong though brittle solid whose particles tend to cohere into
definite geometrical shapes, and sometimes build up frosty
imitations of the most complex forms of vegetable foliage.

Nevertheless we call these, and many other strange phaenomena, the
properties of the water, and we do not hesitate to believe that, in
some way or another, they result from the properties of the
component elements of the water. We do not assume that a something
called "aquosity" entered into and took possession of the oxidated
hydrogen as soon as it was formed, and then guided the aqueous
particles to their places in the facets of the crystal, or amongst
the leaflets of the hoar-frost. On the contrary, we live in the
hope and in the faith that, by the advance of molecular physics, we
shall by and by be able to see our way as clearly from the
constituents of water to the properties of water, as we are now
able to deduce the operations of a watch from the form of its parts
and the manner in which they are put together.

Is the case in any way changed when carbonic acid, water, and
nitrogenous salts disappear, and in their place, under the
influence of pre-existing living protoplasm, an equivalent weight
of the matter of life makes its appearance?

It is true that there is no sort of parity between the properties
of the components and the properties of the resultant, but neither
was there in the case of the water. It is also true that what I
have spoken of as the influence of pre-existing living matter is
something quite unintelligible; but does anybody quite comprehend
the modus operandi [106] of an electric spark, which traverses a
mixture of oxygen and hydrogen?

What justification is there, then, for the assumption of the
existence in the living matter of a something which has no
representative, or correlative, in the not living matter which gave
rise to it? What better philosophical status has "vitality" than
"aquosity"? And why should "vitality" hope for a better fate than
the other "itys" which have disappeared since Martinus Scriblerus [107]
accounted for the operation of the meat-jack [108] by its inherent
"meat-roasting quality," and scorned the "materialism" of those who
explained the turning of the spit by a certain mechanism worked by
the draught of the chimney.

If scientific language is to possess a definite and constant
signification whenever it is employed, it seems to me that we are
logically bound to apply to the protoplasm, or physical basis of
life, the same conceptions as those which are held to be legitimate
elsewhere. If the phaenomena exhibited by water are its
properties, so are those presented by protoplasm, living or dead,
its properties.

If the properties of water may be properly said to result from the
nature and disposition of its component molecules, I can find no
intelligible ground for refusing to say that the properties of
protoplasm result from the nature and disposition of its molecules.

But I bid you beware that, in accepting these conclusions, you are
placing your feet on the first rung of a ladder which, in most
people's estimation, is the reverse of Jacob's, and leads to the
antipodes of heaven. It may seem a small thing to admit that the
dull vital actions of a fungus, or a foraminifer, are the
properties of their protoplasm, and are the direct results of the
nature of the matter of which they are composed. But if, as I have
endeavoured to prove to you, their protoplasm is essentially
identical with, and most readily converted into, that of any
animal, I can discover no logical halting-place between the
admission that such is the case, and the further concession that
all vital action may, with equal propriety, be said to be the
result of the molecular forces of the protoplasm which displays it.
And if so, it must be true, in the same sense and to the same
extent, that the thoughts to which I am now giving utterance, and
your thoughts regarding them, are the expression of molecular
changes in that matter of life which is the source of our other
vital phaenomena.[109]


The marine productions which are commonly known by the names of
"Corals" and "Corallines," were thought by the ancients to be sea-
weeds, which had the singular property of becoming hard and solid,
when they were fished up from their native depths and came into
contact with the air.

"Sic et curalium, quo primum contigit auras
Tempore durescit: mollis fuit herba sub undis,"[111]

says Ovid (Metam. xv); and it was not until the seventeenth century
that Boccone [112] was emboldened, by personal experience of the facts,
to declare that the holders of this belief were no better than
"idiots," who had been misled by the softness of the outer coat of
the living red coral to imagine that it was soft all through.

Messer Boccone's strong epithet is probably undeserved, as the
notion he controverts, in all likelihood, arose merely from the
misinterpretation of the strictly true statement which any coral
fisherman would make to a curious inquirer; namely, that the
outside coat of the red coral is quite soft when it is taken out of
the sea. At any rate, he did good service by eliminating this much
error from the current notions about coral. But the belief that
corals are plants remained, not only in the popular, but in the
scientific mind; and it received what appeared to be a striking
confirmation from the researches of Marsigli [113] in 1706. For this
naturalist, having the opportunity of observing freshly-taken red
coral, saw that its branches were beset with what looked like
delicate and beautiful flowers each having eight petals. It was
true that these "flowers" could protrude and retract themselves,
but their motions were hardly more extensive, or more varied, than
those of the leaves of the sensitive plant; and therefore they
could not be held to militate against the conclusion so strongly
suggested by their form and their grouping upon the branches of a
tree-like structure.

Twenty years later, a pupil of Marsigli, the young Marseilles
physician, Peyssonel, conceived the desire to study these singular
sea-plants, and was sent by the French Government on a mission to
the Mediterranean for that purpose. The pupil undertook the
investigation full of confidence in the ideas of his master, but
being able to see and think for himself, he soon discovered that
those ideas by no means altogether corresponded with reality. In
an essay entitled "Traite du Corail," which was communicated to
the French Academy of Science, but which has never been published,
Peyssonel writes:--

"Je fis fleurir le corail dans des vases pleins d'eau de mer, et
j'observai que ce que nous croyons etre la fleur de cette pretendue
plante n'etait au vrai, qu'un insecte semblable a une petite Ortie
ou Poulpe. J'avais le plaisir de voir remuer les pattes, ou pieds,
de cette Ortie, et ayant mis le vase plein d'eau ou le corail etait
a une douce chaleur aupres du feu, tous les petits insectes
s'epanouirent.--L'Ortie sortie etend les pieds, et forme ce que M.
de Marsigli et moi avions pris pour les petales de la fleur. Le
calice de cette pretendue fleur est le corps meme de l'animal
avance et sorti hors de la cellule."*[114]

* This extract from Peyssonel's manuscript is given by M. Lacaze
Duthiers in his valuable Histoire Naturelle du Corail (1866).

The comparison of the flowers of the coral to a "petite ortie," or
"little nettle," is perfectly just, but needs explanation. "Ortie
de mer," or "sea-nettle," is, in fact, the French appellation for
our "sea-anemone," a creature with which everybody, since the great
aquarium mania, must have become familiar, even to the limits of
boredom. In 1710, the great naturalist, Reaumur,[115] had written a
memoir for the express purpose of demonstrating that these "orties"
are animals; and with this important paper Peyssonel must
necessarily have been familiar. Therefore, when he declared the
"flowers" of the red coral to be little "orties," it was the same
thing as saying that they were animals of the same general nature
as sea-anemones. But to Peyssonel's contemporaries this was an
extremely startling announcement. It was hard to imagine the
existence of such a thing as an association of animals into a
structure with stem and branches altogether like a plant, and fixed
to the soil as a plant is fixed; and the naturalists of that day
preferred not to imagine it. Even Reaumur could not bring himself
to accept the notion, and France being blessed with Academicians,
whose great function (as the late Bishop Wilson [116] and an eminent
modern writer [117] have so well shown) is to cause sweetness and
light to prevail, and to prevent such unmannerly fellows as Peyssonel
from blurting out unedifying truths, they suppressed him; and, as
aforesaid, his great work remained in manuscript, and may at this
day be consulted by the curious in that state, in the Bibliotheque
du Museum d'Histoire Naturelle. Peyssonel, who evidently was a
person of savage and untameable disposition, so far from
appreciating the kindness of the Academicians in giving him time to
reflect upon the unreasonableness, not to say rudeness, of making
public statements in opposition to the views of some of the most
distinguished of their body, seems bitterly to have resented the
treatment he met with. For he sent all further communications to
the Royal Society of London, which never had, and it is to be hoped
never will have, anything of an academic constitution; and finally
he took himself off to Guadaloupe, and became lost to science

Fifteen or sixteen years after the date of Peyssonel's suppressed
paper, the Abbe Trembley [118] published his wonderful researches upon
the fresh-water Hydra. Bernard de Jussieu [119] and Guettard [120]
followed them up by like inquiries upon the marine sea-anemones and
corallines; Reaumur, convinced against his will of the entire justice
of Peyssonel's views, adopted them, and made him a half-and-half
apology in the preface to the next published volume of the
"Memoires pour servir l'Histoire des Insectes;" and, from this time
forth, Peyssonel's doctrine that corals are the work of animal
organisms has been part of the body of established scientific

Peyssonel, in the extract from his memoir already cited, compares
the flower-like animal of the coral to a "poulpe," which is the
French form of the name "polypus,"--"the many-footed,"--which the
ancient naturalists gave to the soft-bodied cuttlefishes, which,
like the coral animal, have eight arms, or tentacles, disposed
around a central mouth. Reaumur, admitting the analogy indicated
by Peyssonel, gave the name of polypes, not only to the sea-
anemone, the coral animal, and the fresh-water Hydra, but to what
are now known as the Polyzoa, and he termed the skeleton which they
fabricate a "polypier," or "polypidom."

The progress of discovery, since Reaumur's time, has made us very
completely acquainted with the structure and habits of all these
polypes. We know that, among the sea-anemones and coral-forming
animals, each poylpe has a mouth leading to a stomach, which is
open at its inner end, and thus communicates freely with the
general cavity of the body; that the tentacles placed round the
mouth are hollow, and that they perform the part of arms in seizing
and capturing prey. It is known that many of these creatures are
capable of being multiplied by artificial division, the divided
halves growing, after a time, into complete and separate animals;
and that many are able to perform a very similar process naturally,
in such a manner that one polype may, by repeated incomplete
divisions, give rise to a sort of sheet, or turf, formed by
innumerable connected, and yet independent, descendants. Or, what
is still more common, a polype may throw out buds, which are
converted into polypes, or branches bearing polypes, until a tree-
like mass, sometimes of very considerable size, is formed.

This is what happens in the case of the red coral of commerce. A
minute polype, fixed to the rocky bottom of the deep sea, grows up
into a branched trunk. The end of every branch and twig is
terminated by a polype; and all the polypes are connected together
by a fleshy substance, traversed by innumerable canals which place
each polype in communication with every other, and carry
nourishment to the substance of the supporting stem. It is a sort
of natural cooperative store, every polype helping the whole, at
the same time as it helps itself. The interior of the stem, like
that of the branches, is solidified by the deposition of carbonate
of lime in its tissue, somewhat in the same fashion as our own
bones are formed of animal matter impregnated with lime salts; and
it is this dense skeleton (usually turned red by a peculiar
colouring matter) cleared of the soft animal investment, as the
hard wood of a tree might be stripped of its bark, which is the red

In the case of the red coral, the hard skeleton belongs to the
interior of the stem and branches only; but in the commoner white
corals, each polype has a complete skeleton of its own. These
polypes are sometimes solitary, in which case the whole skeleton is
represented by a single cup, with partitions radiating from its
centre to its circumference. When the polypes formed by budding or
division remain associated, the polypidom is sometimes made up of
nothing but an aggregation of these cups, while at other times the
cups are at once separated and held together, by an intermediate
substance, which represents the branches of the red coral. The red
coral polype again is a comparatively rare animal, inhabiting a
limited area, the skeleton of which has but a very insignificant
mass; while the white corals are very common, occur in almost all
seas, and form skeletons which are sometimes extremely massive.

With a very few exceptions, both the red and the white coral
polypes are, in their adult state, firmly adherent to the sea-
bottom; nor do their buds naturally become detached and locomotive.
But, in addition to budding and division, these creatures possess
the more ordinary methods of multiplication; and, at particular
seasons, they give rise to numerous eggs of minute size. Within
these eggs the young are formed, and they leave the egg in a
condition which has no sort of resemblance to the perfect animal.
It is, in fact, a minute oval body, many hundred times smaller than
the full grown creature, and it swims about with great activity by
the help of multitudes of little hair-like filaments, called cilia,
with which its body is covered. These cilia all lash the water in
one direction, and so drive the little body along as if it were
propelled by thousands of extremely minute paddles. After enjoying
its freedom for a longer or shorter time, and being carried either
by the force of its own cilia, or by currents which bear it along,
the embryo coral settles down to the bottom, loses its cilia, and
becomes fixed to the rock, gradually assuming the polype form and
growing up to the size of its parent. As the infant polypes of the
coral may retain this free and active condition for many hours, or
even days, and as a tidal or other current in the sea may easily
flow at the speed of two or even more miles in an hour, it is clear
that the embryo must often be transported to very considerable
distances from the parent. And it is easily understood how a
single polype, which may give rise to hundreds, or perhaps
thousands, of embryos, may, by this process of partly active and
partly passive migration, cover an immense surface with its

The masses of coral which may be formed by the assemblages of
polypes which spring by budding, or by dividing, from a single
polype, occasionally attain very considerable dimensions. Such
skeletons are sometimes great plates, many feet long and several
feet in thickness; or they may form huge half globes, like the
brainstone corals, or may reach the magnitude of stout shrubs or
even small trees. There is reason to believe that such masses as
these take a long time to form, and hence that the age a polype
tree, or polype turf, may attain, may be considerable. But, sooner
or later, the coral polypes, like all other things, die; the soft
flesh decays, while the skeleton is left as a stony mass at the
bottom of the sea, where it retains its integrity for a longer or a
shorter time, according as its position affords more or less
protection from the wear and tear of the waves.

The polypes which give rise to the white coral are found, as has
been said, in the seas of all parts of the world; but in the
temperate and cold oceans they are scattered and comparatively
small in size, so that the skeletons of those which die do not
accumulate in any considerable quantity. But it is otherwise in
the greater part of the ocean which lies in the warmer parts of the
world, comprised within a distance of about eighteen hundred miles
on each side of the equator. Within the zone thus bounded, by far
the greater part of the ocean is inhabited by coral polypes, which
not only form very strong and large skeletons, but associate
together into great masses, like the thickets and the meadow turf,
or, better still, the accumulations of peat, to which plants give
rise on dry land. These masses of stony matter, heaped up beneath
the waters of the ocean, become as dangerous to mariners as so much
ordinary rock, and to these, as to the common rock ridges, the
seaman gives the name of "reefs."

Such coral reefs cover many thousand square miles in the Pacific
and in the Indian Oceans. There is one reef, or rather great
series of reefs, called the Barrier Reef, which stretches, almost
continuously, for more than eleven hundred miles off the east coast
of Australia. Multitudes of the islands in the Pacific are either
reefs themselves, or are surrounded by reefs. The Red Sea is in
many parts almost a maze of such reefs, and they abound no less in
the West Indies, along the coast of Florida, and even as far north
as the Bahama Islands. But it is a very remarkable circumstance
that, within the area of what we may call the "coral zone," there
are no coral reefs upon the west coast of America, nor upon the
west coast of Africa; and it is a general fact that the reefs are
interrupted, or absent, opposite the mouths of great rivers. The
causes of this apparent caprice in the distribution of coral reefs
are not far to seek. The polypes which fabricate them require for
their vigorous growth a temperature which must not fall below 68
degrees Fahrenheit all the year round, and this temperature is only
to be found within the distance on each side of the equator which
has been mentioned, or thereabouts. But even within the coral zone
this degree of warmth is not everywhere to be had. On the west
coast of America, and on the corresponding coast of Africa, the
currents of cold water from the icy regions which surround the
South Pole set northward, and it appears to be due to their cooling
influence that the sea in these regions is free from the reef
builders. Again, the coral polypes cannot live in water which is
rendered brackish by floods from the land, or which is perturbed by
mud from the same source, and hence it is that they cease to exist
opposite the mouths of rivers, which damage them in both these

Such is the general distribution of the reef-building corals, but
there are some very interesting and singular circumstances to be
observed in the conformation of the reefs, when we consider them
individually. The reefs, in fact, are of three different kinds;
some of them stretch out from the shore, almost like a prolongation
of the beach, covered only by shallow water, and in the case of an
island, surrounding it like a fringe of no considerable breadth.
These are termed "fringing reefs." Others are separated by a
channel which may attain a width of many miles, and a depth of
twenty or thirty fathoms or more, from the nearest land; and when
this land is an island, the reef surrounds it like a low wall, and
the sea between the reef and the land is, as it were, a moat inside
this wall. Such reefs as these are called "encircling" when they
surround an island; and "barrier" reefs, when they stretch parallel
with the coast of a continent. In both these cases there is
ordinary dry land inside the reef, and separated from it only by a
narrower or a wider, a shallower or a deeper, space of sea, which
is called a "lagoon," or "inner passage." But there is a third kind
of reef, of very common occurrence in the Pacific and Indian
Oceans, which goes by the name of "atoll." This is, to all intents
and purposes, an encircling reef, without anything to encircle; or,
in other words, without an island in the middle of its lagoon. The
atoll has exactly the appearance of a vast, irregularly oval, or
circular, breakwater, enclosing smooth water in its midst. The
depth of the water in the lagoon rarely exceeds twenty or thirty
fathoms, but, outside the reef, it deepens with great rapidity to
two hundred or three hundred fathoms. The depth immediately
outside the barrier, or encircling, reefs, may also be very
considerable; but, at the outer edge of a fringing reef, it does
not amount usually to more than twenty or twenty-five fathoms; in
other words, from one hundred and twenty to one hundred and fifty

Thus, if the water of the ocean should be suddenly drained away, we
should see the atolls rising from the sea-bed like vast truncated
cones, and resembling so many volcanic craters, except that their
sides would be steeper than those of an ordinary volcano. In the
case of the encircling reefs, the cone, with the enclosed island,
would look like Vesuvius with Monte Nuovo within the old crater of
Somma;[121] while, finally, the island with a fringing reef would
have the appearance of an ordinary hill, or mountain, girded by a vast
parapet, within which would lie a shallow moat. And the dry bed of
the Pacific might afford grounds for an inhabitant of the moon to
speculate upon the extraordinary subterranean activity to which
these vast and numerous "craters" bore witness!

When the structure of a fringing reef is investigated, the bottom
of the lagoon is found to be covered with fine whitish mud, which
results from the breaking up of the dead corals. Upon this muddy
floor there lie, here and there, growing corals, or occasionally
great blocks of dead coral, which have been torn by storms from the
outer edge of the reef, and washed into the lagoon. Shellfish and
worms of various kinds abound; and fish, some of which prey upon
the coral, sport in the deeper pools. But the corals which are to
be seen growing in the shallow waters of the lagoon are of a
different kind from those which abound on the outer edge of the
reef, and of which the reef is built up. Close to the seaward edge
of the reef, over which, even in calm weather, a surf almost always
breaks, the coral rock is encrusted with a thick coat of a singular
vegetable organism, which contains a great deal of lime--the so-
called Nullipora. Beyond this, in the part of the edge of the reef
which is always covered by the breaking waves, the living, true,
reef-polypes make their appearance; and, in different forms, coat
the steep seaward face of the reef to a depth of one hundred or
even one hundred and fifty feet. Beyond this depth the sounding-
lead rests, not upon the wall-like face of the reef, but on the
ordinary shelving sea-bottom. And the distance to which a fringing
reef extends from the land corresponds with that at which the sea
has a depth of twenty or five-and-twenty fathoms.

If, as we have supposed, the sea could be suddenly withdrawn from
around an island provided with a fringing reef, such as the
Mauritius,[122] the reef would present the aspect of a terrace,
its seaward face, one hundred feet or more high, blooming with the
animal flowers of the coral, while its surface would be hollowed
out into a shallow and irregular moat-like excavation.

The coral mud, which occupies the bottom of the lagoon, and with
which all the interstices of the coral skeletons which accumulate
to form the reef are filled up, does not proceed from the washing
action of the waves alone; innumerable fishes, and other creatures
which prey upon the coral, add a very important contribution of
finely-triturated calcareous matter; and the corals and mud
becoming incorporated together, gradually harden and give rise to a
sort of limestone rock, which may vary a good deal in texture.
Sometimes it remains friable and chalky, but, more often, the
infiltration of water, charged with carbonic acid, dissolves some
of the calcareous matter, and deposits it elsewhere in the
interstices of the nascent rock, thus glueing and cementing the
particles together into a hard mass; or it may even dissolve the
carbonate of lime more extensively, and re-deposit it in a
crystalline form. On the beach of the lagoon, where the coral sand
is washed into layers by the action of the waves, its grains become
thus fused together into strata of a limestone, so hard that they
ring when struck with a hammer, and inclined at a gentle angle,
corresponding with that of the surface of the beach. The hard
parts of the many animals which live upon the reef become imbedded
in this coral limestone, so that a block may be full of shells of
bivalves and univalves, or of sea urchins; and even sometimes
encloses the eggs of turtles in a state of petrification. The
active and vigorous growth of the reef goes on only at the seaward
margins, where the polypes are exposed to the wash of the surf, and
are thereby provided with an abundant supply of air and of food.
The interior portion of the reef may be regarded as almost wholly
an accumulation of dead skeletons. Where a river comes down from
the land there is a break in the reef, for the reasons which have
been already mentioned.

The origin and mode of formation of a fringing reef, such as that
just described, are plain enough. The embryos of the coral polypes
have fixed themselves upon the submerged shore of the island, as
far out as they could live, namely, to a depth of twenty or twenty-
five fathoms. One generation has succeeded another, building
itself up upon the dead skeletons of its predecessor. The mass has
been consolidated by the infiltration of coral mud, and hardened by
partial solution and redeposition, until a great rampart of coral
rock one hundred or one hundred and fifty feet high on its seaward
face has been formed all round the island, with only such gaps as
result from the outflow of rivers, in the place of sally-ports.

The structure of the rocky accumulation in the encircling reefs and
in the atolls is essentially the same as in the fringing reef.
But, in addition to the differences of depth inside and out, they
present some other peculiarities. These reefs, and especially the
atolls, are usually interrupted at one part of their circumference,
and this part is always situated on the leeward side of the reef,
or that which is the more sheltered side. Now, as all these reefs
are situated within the region in which the tradewinds prevail, it
follows that, on the north side of the equator, where the trade-
wind is a northeasterly wind, the opening of the reef is on the
southwest side: while in the southern hemisphere, where the trade-
winds blow from the southeast, the opening lies to the northwest.
The curious practical result follows from this structure, that the
lagoons to these reefs really form admirable harbours, if a ship
can only get inside them. But the main difference between the
encircling reefs and the atolls, on the one hand, and the fringing
reefs on the other, lies in the fact of the much greater depth of
water on the seaward faces of the former. As a consequence of this
fact, the whole of this face is not, as it is in the case of the
fringing reef, covered with living coral polypes. For, as we have
seen, these polypes cannot live at a greater depth than about
twenty-five fathoms; and actual observation has shown that while,
down to this depth, the sounding-lead will bring up branches of
live coral from the outer wall of such a reef, at a greater depth
it fetches to the surface nothing but dead coral and coral sand.
We must, therefore, picture to ourselves an atoll, or an encircling
reef, as fringed for one hundred feet, or more, from its summit,
with coral polypes busily engaged in fabricating coral; while,
below this comparatively narrow belt, its surface is a bare and
smooth expanse of coral sand, supported upon and within a core of
coral limestone. Thus, if the bed of the Pacific were suddenly
laid bare, as was just now supposed, the appearance of the reef-
mountains would be exactly the reverse of that presented by many
high mountains on land. For these are white with snow at the top,
while their bases are clothed with an abundant and gaudily-coloured
vegetation. But the coral cones would look grey and barren below,
while their summits would be gay with a richly-coloured parterre of
flowerlike coral polypes.

The practical difficulties of sounding upon, and of bringing up
portions of, the seaward face of an atoll or of an encircling reef,
are so great, in consequence of the constant and dangerous swell
which sets towards it, that no exact information concerning the
depth to which the reefs are composed of coral has yet been
obtained. There is no reason to doubt, however, that the reef-cone
has the same structure from its summit to its base, and that its
sea-wall is throughout mainly composed of dead coral.

And now arises a serious difficulty. If the coral polypes cannot
live at a greater depth than one hundred or one hundred and fifty
feet, how can they have built up the base of the reef-cone, which
may be two thousand feet, or more, below the surface of the sea?

In order to get over this objection, it was at one time supposed
that the reef-building polypes had settled upon the summits of a
chain of submarine mountains. But what is there in physical
geography to justify the assumption of the existence of a chain of
mountains stretching for one thousand miles or more, and so nearly
of the same height, that none should rise above the level of the
sea, nor fall one hundred and fifty feet below that level?

How, again, on this hypothesis, are atolls to be accounted for,
unless, as some have done, we take refuge in the wild supposition
that every atoll corresponds with the crater of a submarine
volcano? And what explanation does it afford of the fact that, in
some parts of the ocean, only atolls and encircling reefs occur,
while others present none but fringing reefs?

These and other puzzling facts remained insoluble until the
publication, in the year 1840, of Mr. Darwin's famous work on coral
reefs;[123] in which a key was given to all the difficult problems
connected with the subject, and every difficulty was shown to be
capable of solution by deductive reasoning from a happy combination
of certain well-established geological and biological truths. Mr.
Darwin, in fact, showed that, so long as the level of the sea
remains unaltered in any area in which coral reefs are being
formed, or if the level of the sea relatively to that of the land
is falling, the only reefs which can be formed are fringing reefs.
While if, on the contrary, the level of the sea is rising
relatively to that of the land, at a rate not faster than that at
which the upward growth of the coral can keep pace with it, the
reef will gradually pass from the condition of a fringing, into
that of an encircling or barrier reef. And, finally, that if the
relative level of the sea rise so much that the encircled land is
completely submerged, the reef must necessarily pass into the
condition of an atoll.

For, suppose the relative level of the sea to remain stationary,
after a fringing reef has reached that distance from the land at
which the depth of water amounts to one hundred and fifty feet.
Then the reef cannot extend seaward by the migration of coral
germs, because these coral germs would find the bottom of the sea
to be too deep for them to live in. And the only manner in which
the reef could extend outwards, would be by the gradual
accumulation, at the foot of its seaward face, of a talus of coral
fragments torn off by the violence of the waves, which talus might,
in course of time, become high enough to bring its upper surface
within the limits of coral growth, and in that manner provide a
sort of factitious sea-bottom upon which the coral embryos might
perch. If, on the other hand, the level of the sea were slowly and
gradually lowered, it is clear that the parts of its bottom
originally beyond the limit of coral growth would gradually be
brought within the required distance of the surface, and thus the
reef might be indefinitely extended. But this process would give
rise neither to an encircling reef nor to an atoll, but to a broad
belt of upheaved coral rock, increasing the dimensions of the dry
land, and continuous seawards with the fresh fringing reef.

Suppose, however, that the sea-level rose instead of falling, at
the same slow and gradual rate at which we know it to be rising in
some parts of the world,--not more, in fact, than a few inches, or,
at most, a foot or two, in a hundred years. Then, while the reef
would be unable to extend itself seaward, the sea-bottom outside it
being gradually more and more removed from the depth at which the
life of the coral polypes is possible, it would be able to grow
upwards as fast as the sea rose. But the growth would take place
almost exclusively around the circumference of the reef, this being
the only region in which the coral polypes would find the
conditions favourable for their existence. The bottom of the
lagoon would be raised, in the main, only by the coral debris and
coral mud, formed in the manner already described; consequently,
the margins of the reef would rise faster than the bottom, or, in
other words, the lagoon would constantly become deeper. And, at
the same time, it would gradually increase in breadth; as the
rising sea, covering more of the land, would occupy a wider space
between the edge of the reef and what remained of the land. Thus
the rising sea would eventually convert a large island with a
fringing reef into a small island surrounded by an encircling reef.
And it will be obvious that when the rising of the sea has gone so
far as completely to cover the highest points of the island, the
reef will have passed into the condition of an atoll.

But how is it possible that the relative level of the land and sea
should be altered to this extent? Clearly, only in one of two
ways: either the sea must have risen over those areas which are now
covered by atolls and encircling reefs; or, the land upon which the
sea rests must have been depressed to a corresponding extent.

If the sea has risen, its rise must have taken place over the whole
world simultaneously, and it must have risen to the same height
over all parts of the coral zone. Grounds have been shown for the
belief that the general level of the sea may have been different at
different times; it has been suggested, for example, that the
accumulation of ice about the poles during one of the cold periods
of the earth's history necessarily implies a diminution in the
volume of the sea proportioned to the amount of its water thus
permanently locked up in the Arctic and Antarctic ice-cellars;
while, in the warm periods, the greater or less disappearance of
the polar ice-cap implies a corresponding addition of water to the
ocean. And no doubt this reasoning must be admitted to be sound in
principle; though it is very hard to say what practical effect the
additions and subtractions thus made have had on the level of the
ocean; inasmuch as such additions and subtractions might be either
intensified or nullified, by contemporaneous changes in the level
of the land. And no one has yet shown that any such great melting
of polar ice, and consequent raising of the level of the water of
the ocean, has taken place since the existing atolls began to be

In the absence of any evidence that the sea has ever risen to the
extent required to give rise to the encircling reefs and the
atolls, Mr. Darwin adopted the opposite hypothesis, viz., that the
land has undergone extensive and slow depression in those
localities in which these structures exist.

It seems, at first, a startling paradox, to suppose that the land
is less fixed than the sea; but that such is the case is the
uniform testimony of geology. Beds of sandstone or limestone,
thousands of feet thick, and all full of marine remains, occur in
various parts of the earth's surface, and prove, beyond a doubt,
that when these beds were formed, that portion of the sea-bottom
which they then occupied underwent a slow and gradual depression to
a distance which cannot have been less than the thickness of those
beds, and may have been very much greater. In supposing,
therefore, that the great areas of the Pacific and of the Indian
Ocean, over which atolls and encircling reefs are found scattered,
have undergone a depression of some hundreds, or, it may be,
thousands of feet, Mr. Darwin made a supposition which had nothing
forced or improbable, but was entirely in accordance with what we
know to have taken place over similarly extensive areas, in other
periods of the world's history. But Mr. Darwin subjected his
hypothesis to an ingenious indirect test. If his view be correct,
it is clear that neither atolls, nor encircling reefs, should be
found in those portions of the ocean in which we have reason to
believe, on independent grounds, that the sea-bottom has long been
either stationary, or slowly rising. Now it is known that, as a
general rule, the level of the land is either stationary, or is
undergoing a slow upheaval, in the neighborhood of active
volcanoes; and, therefore, neither atolls nor encircling reefs
ought to be found in regions in which volcanoes are numerous and
active. And this turns out to be the case. Appended to Mr.
Darwin's great work on coral reefs, there is a map on which atolls
and encircling reefs are indicated by one colour, fringing reefs by
another, and active volcanoes by a third. And it is at once
obvious that the lines of active volcanoes lie around the margins
of the areas occupied by the atolls and the encircling reefs. It
is exactly as if the upheaving volcanic agencies had lifted up the
edges of these great areas, while their centres had undergone a
corresponding depression. An atoll area may, in short, be pictured
as a kind of basin, the margins of which have been pushed up by the
subterranean forces, to which the craters of the volcanoes have, at
intervals, given vent.

Thus we must imagine the area of the Pacific now covered by the
Polynesian Archipelago, as having been, at some former time,
occupied by large islands, or, may be, by a great continent, with
the ordinarily diversified surface of plain, and hill, and mountain
chain. The shores of this great land were doubtless fringed by
coral reefs; and, as it slowly underwent depression, the hilly
regions, converted into islands, became, at first, surrounded by
fringing reefs, and then, as depression went on, these became
converted into encircling reefs, and these, finally, into atolls,
until a maze of reefs and coral-girdled islets took the place of
the original land masses.

Thus the atolls and the encircling reefs furnish us with clear,
though indirect, evidence of changes in the physical geography of
large parts of the earth's surface; and even, as my lamented
friend, the late Professor Jukes,[124] has suggested, give us
indications of the manner in which some of the most puzzling facts
connected with the distribution of animals have been brought about.
For example, Australia and New Guinea are separated by Torres
Straits, a broad belt of sea one hundred or one hundred and twenty
miles wide. Nevertheless, there is in many respects a curious
resemblance between the land animals which inhabit New Guinea and
the land animals which inhabit Australia. But, at the same time,
the marine shellfish which are found in the shallow waters of the
shores of New Guinea are quite different from those which are met
with upon the coasts of Australia. Now, the eastern end of Torres
Straits is full of atolls, which, in fact, form the northern
termination of the Great Barrier Reef which skirts the eastern
coast of Australia. It follows, therefore, that the eastern end of
Torres Straits is an area of depression, and it is very possible,
and on many grounds highly probable, that, in former times,
Australia and New Guinea were directly connected together, and that
Torres Straits did not exist. If this were the case, the existence
of cassowaries and of marsupial quadrupeds, both in New Guinea and
in Australia, becomes intelligible; while the difference between
the littoral molluscs of the north and the south shores of Torres
Straits is readily explained by the great probability that, when
the depression in question took place, and what was, at first, an
arm of the sea became converted into a strait separating Australia
from New Guinea, the northern shore of this new sea became tenanted
with marine animals from the north, while the southern shore was
peopled by immigrants from the already existing marine Australian

Inasmuch as the growth of the reef depends upon that of successive
generations of coral polypes, and as each generation takes a
certain time to grow to its full size, and can only separate its
calcareous skeleton from the water in which it lives at a certain
rate, it is clear that the reefs are records not only of changes in
physical geography, but of the lapse of time. It is by no means
easy, however, to estimate the exact value of reef chronology, and
the attempts which have been made to determine the rate at which a
reef grows vertically have yielded anything but precise results. A
cautious writer, Mr. Dana,[125] whose extensive study of corals and
coral reefs makes him an eminently competent judge, states his
conclusion in the following terms:--

"The rate of growth of the common branching madrepore is not over
one and a half inches a year. As the branches are open, this would
not be equivalent to more than half an inch in height of solid
coral for the whole surface covered by the madrepore; and, as they
are also porous, to not over three-eighths of an inch of solid
limestone. But a coral plantation has large bare patches without
corals, and the coral sands are widely distributed by currents,
part of them to depths over one hundred feet where there are no
living corals; not more than one-sixth of the surface of a reef
region is, in fact, covered with growing species. This reduces the
three-eighths to ONE-SIXTEENTH. Shells and other organic relics
may contribute one-fourth as much as corals. At the outside, the
average upward increase of the whole reef-ground per year would not
exceed ONE-EIGHTH of an inch.

"Now some reefs are at least two thousand feet thick, which at one-
eighth of an inch a year, corresponds to one hundred and ninety-two
thousand years."*

* Dana, Manual of Geology, p. 591.

Halve, or quarter, this estimate if you will, in order to be
certain of erring upon the right side, and still there remains a
prodigious period during which the ancestors of existing coral
polypes have been undisturbedly at work; and during which,
therefore, the climatal conditions over the coral area must have
been much what they are now.

And all this lapse of time has occurred within the most recent
period of the history of the earth. The remains of reefs formed by
coral polypes of different kinds from those which exist now, enter
largely into the composition of the limestones of the Jurassic
period;[126] and still more widely different coral polypes have
contributed their quota to the vast thickness of the carboniferous
and Devonian strata. Then as regards the latter group of rocks in
America, the high authority already quoted tells us:--

"The Upper Helderberg period is eminently the coral reef period of
the palaeozoic ages. Many of the rocks abound in coral, and are as
truly coral reefs as the modern reefs of the Pacific. The corals
are sometimes standing on the rocks in the position they had when
growing: others are lying in fragments, as they were broken and
heaped by the waves; and others were reduced to a compact limestone
by the finer trituration before consolidation into rock. This
compact variety is the most common kind among the coral reef rocks
of the present seas; and it often contains but few distinct
fossils, although formed in water that abounded in life. At the
fall of the Ohio, near Louisville, there is a magnificent display
of the old reef. Hemispherical Favosites, five or six feet in
diameter, lie there nearly as perfect as when they were covered by
their flowerlike polypes; and besides these, there are various
branching corals, and a profusion of Cyathophyllia, or cup-

* Dana, Manual of Geology, p. 272.

Thus, in all the great periods of the earth's history of which we
know anything, a part of the then living matter has had the form of
polypes, competent to separate from the water of the sea the
carbonate of lime necessary for their own skeletons. Grain by
grain, and particle by particle, they have built up vast masses of
rock, the thickness of which is measured by hundreds of feet, and
their area by thousands of square miles. The slow oscillations of
the crust of the earth, producing great changes in the distribution
of land and water, have often obliged the living matter of the
coral-builders to shift the locality of its operations; and, by
variation and adaptation to these modifications of condition, its
forms have as often changed. The work it has done in the past is,
for the most part, swept away, but fragments remain, and, if there
were no other evidence, suffice to prove the general constancy of
the operations of Nature in this world, through periods of almost
inconceivable duration.



Autobiography: Huxley's account of this sketch, written in 1889, is
as follows: "A man who is bringing out a series of portraits of
celebrities, with a sketch of their career attached, has bothered
me out of my life for something to go with my portrait, and to
escape the abominable bad taste of some of the notices, I have done

pre-Boswellian epoch: the time before Boswell. James Boswell
(1740-1795) wrote the famous Life of Samuel Johnson. Mr. Leslie
Stephen declares that this book "became the first specimen of a new
literary type." "It is a full-length portrait of a man's domestic
life with enough picturesque detail to enable us to see him through
the eyes of private friendship. . . ." A number of biographers
since Boswell have imitated his method; and Leslie Stephen believes
that "we owe it in some degree to his example that we have such
delightful books as Lockhart's Life of Scott or Mr. Trevelyan's
Life of Macaulay."

"Bene qui latuit, bene vixit": from Ovid. He who has kept himself
well hidden, has lived well.

Prince George of Cambridge: the grandson of King George III, second
Duke of Cambridge, and Commander-in-chief of the British Army.

Mr. Herbert Spencer (1820--1903): a celebrated English philosopher
and powerful advocate of the doctrine of evolution. Spencer is
regarded as one of the most profound thinkers of modern times. He
was one of Huxley's closest friends.

in partibus infidelium: in the domain of the unbelievers.

"sweet south upon a bed of violets." Cf. Twelfth Night, Act I, sc.
I, l. 5.

O, it came o'er my ear like the sweet sound
That breathes upon a bank of violets,
Stealing and giving odour.

For the reading "sweet south" instead of "sweet sound," see Rolfe's
edition of Twelfth Night.

"Lehrjahre": apprenticeship.

Charing Cross School of Medicine: a school connected with the
Charing Cross Hospital in the Strand, London.

Nelson: Horatio Nelson, a celebrated English Admiral born in
Norfolk, England, 1758, and died on board the Victory at Trafalgar,
1805. It was before the battle off Cape Trafalgar that Nelson
hoisted his famous signal, "England expects every man will do his
duty." Cf. Tennyson's Ode to the Duke of Wellington, stanza VI,
for a famous tribute to Nelson.

middies: abbreviated form for midshipmen.

Suites a Buffon: sequels to Buffon. Buffon (1707-1781) was a
French naturalist who wrote many volumes on science.

Linnean Society: a scientific society formed in 1788 under the
auspices of several fellows of the Royal Society.

Royal Society: The Royal Society for Improving Natural Knowledge;
the oldest scientific society in Great Britain, and one of the
oldest in Europe. It was founded by Charles II, in 1660, its
nucleus being an association of learned men already in existence.
It is supposed to be identical with the Invisible College which
Boyle mentions in 1646. It was incorporated under the name of The
Royal Society in 1661. The publications of the Royal Society are
called Philosophical Transactions. The society has close
connection with the government, and has assisted the government in
various important scientific undertakings among which may be
mentioned Parry's North Pole expedition. The society also
distributes $20,000 yearly for the promotion of scientific

Rastignac: a character in Le Pere Goriot. At the close of the
story Rastignac says, "A nous deux, maintenant":--Henceforth there
is war between us.

Pere Goriot: a novel of Balzac's with a plot similar to King Lear.

Professor Tyndall (1820-1893): a distinguished British physicist
and member of the Royal Society. He explored with Huxley the
glaciers of Switzerland. His work in electricity, radiant heat,
light and acoustics gave him a foremost place in science.

Ecclesiastical spirit: the spirit manifested by the clergy of
England in Huxley's time against the truths of science. The clergy
considered scientific truth to be disastrous to religious truth.
Huxley's attitude toward the teaching of religious truth is
illuminated by this quotation, which he uses to explain his own
position: "I have the fullest confidence that in the reading and
explaining of the Bible, what the children will be taught will be
the great truths of Christian Life and conduct, which all of us
desire they should know, and that no effort will be made to cram
into their poor little minds, theological dogmas which their tender
age prevents them from understanding." Huxley defines his idea of
a church as a place in which, "week by week, services should be
devoted, not to the iteration of abstract propositions in theology,
but to the setting before men's minds of an ideal of true, just and
pure living; a place in which those who are weary of the burden of
daily cares should find a moment's rest in the contemplation of the
higher life which is possible for all, though attained by so few; a
place in which the man of strife and of business should have time
to think how small, after all, are the rewards he covets compared
with peace and charity."

New Reformation: Huxley writes: "We are in the midst of a gigantic
movement greater than that which preceded and produced the
Reformation, and really only the continuation of that movement. . . .
But this organization will be the work of generations of men,
and those who further it most will be those who teach men to rest
in no lie, and to rest in no verbal delusion."


On the Advisableness of Improving Natural Knowledge: from Method
and Results: also published in Lay Sermons, Addresses and Reviews.

For the history of the times mentioned in this essay, see Green's
Short History of the English People.

The very spot: St. Martin's Borough Hall and Public Library, on
Charing Cross Road, near Trafalgar Square.

Defoe (1661-1731): an English novelist and political writer. On
account of his political writings Defoe was sentenced to stand in
the pillory, and to be "imprisoned during the Queen's pleasure."
During this imprisonment he wrote many articles. Later in life he
wrote Robinson Crusoe, The Fortunes and Misfortunes of Moll
Flanders, Journal of the Plague Year, and other books less well

unholy cursing and crackling wit of the Rochesters and Sedleys:
John Wilmot, the second Earl of Rochester, and Sir Charles Sedley,
were both friends of Charles II, and were noted for biting wit and
profligacy. Green, in his Short History of the English People,
thus describes them: "Lord Rochester was a fashionable poet, and
the titles of some of his poems are such as no pen of our day could
copy. Sir Charles Sedley was a fashionable wit, and the foulness
of his words made even the porters in the Covent Garden belt him
from the balcony when he ventured to address them."

Laud: Archbishop of Canterbury. Laud was born in 1573, and
beheaded at London in 1645. He was throughout the reign of Charles
I a staunch supporter of the King. He was impeached by the Long
Parliament in 1640 and executed on Tower Hill, in 1645.

selenography: the scientific study of the moon with special
reference to its physical condition.

Torricellian experiment: a reference to the discovery of the
principle of the barometer by the Italian, Torricelli, in 1643.

Sir Francis Bacon (1561-1626): Bacon endeavored to teach that
civilization cannot be brought to a high point except as man
applies himself to the study of the secrets of nature, and uses
these discoveries for inventions which will give him power over his
environment. The chief value of the work was that it called
attention to the uses of induction and to the experimental study of
facts. See Roger's A Student's History of Philosophy, page 243.

The learned Dr. Wallis (1616-1703): Dr. Wallis is regarded as the
greatest of Newton's predecessors in mathematical history. His
works are numerous and are on a great variety of subjects. He was
one of the first members of the Royal Society.

"New Philosophy": Bacon's ideas on science and philosophy as set
forth in his works.

Royal Society: see note, page 11.

Newton, Sir Isaac (1642-1721): a distinguished natural philosopher
of England. Newton was elected a member of the Royal Society in
1672. His most important scientific accomplishment was the
establishing of the law of universal gravitation. The story of the
fall of the apple was first related by Voltaire to whom it was
given by Newton's niece.

"Philosophical Transactions": the publications of the Royal

Galileo (1564-1642): a famous Italian astronomer. His most noted
work was the construction of the thermometer and a telescope. He
discovered the satellites of Jupiter in 1610. In 1610, also, he
observed the sun's spots. His views were condemned by the Pope in
1616 and in 1633 he was forced by the Inquisition to abjure the
Copernican theory.

Vesalius (1514-1564): a noted Belgian anatomist.

Harvey (1578-1657): an English physiologist and anatomist. He is
noted especially for his discovery of the circulation of the blood.

Subtle speculations: Selby gives examples from questions discussed
by Thomas Aquinas. Whether all angels belong to the same genus,
whether demons are evil by nature, or by will, whether they can
change one substance into another, . . . whether an angel can move
from one point to another without passing through intermediate

Schoolmen: a term used to designate the followers of scholasticism,
a philosophy of dogmatic religion which assumed a certain subject-
matter as absolute and unquestionable. The duty of the Schoolman
was to explain church doctrine; these explanations were
characterized by fine distinctions and by an absence of real
content. See Roger's A Student's History of Philosophy; also
Baldwin's Dictionary of Philosophy and Psychology.

"writ in water": an allusion to Keats' request that the words "Here
lies one whose name was writ in water" be his epitaph. The words
are inscribed on his tomb in the Protestant Cemetery at Rome.

Lord Brouncker: The first president of the Royal Society after its
incorporation in 1662 was Lord Brouneker.

revenant: ghost.

Boyle: Robert Boyle (1627-1691): a British chemist and natural
philosopher who was noted especially for his discovery of Boyle's
law of the elasticity of air.

Evelyn (1620-1706): an English author and member of the Royal
Society. His most important work is the Diary, valuable for the
full account which it gives of the manners and customs of the time.

The Restoration: In English history the re-establishing of the
English monarchy with the return of King Charles II in 1660; by
extension the whole reign of Charles II: as, the dramatists of the
Restoration. Century Dictionary.

Aladdin's lamps: a reference to the story of the Wonderful Lamp in
the Arabian Nights. The magic lamp brought marvelous good fortune
to the poor widow's son who possessed it. Cf. also Lowell's

When I was a beggarly boy,
And lived in a cellar damp,
I had not a friend or a toy,
But I had Aladdin's lamp;
When I could not sleep for the cold,
I had fire enough in my brain,
And builded, with roofs of gold,
My beautiful castles in Spain!

"When in heaven the stars": from Tennyson's Specimens of a
Translation of the Iliad in Blank Verse.

"increasing God's honour and bettering man's estate": Bacon's
statement of his purpose in writing the Advancement of Learning.

For example, etc.: could the sentence beginning thus be written in
better form?

Rumford (1738-1814): Benjamin Thompson, Count Rumford, an eminent
scientist. Rumford was born in America and educated at Harvard.
Suspected of loyalty to the King at the time of the revolution, he
was imprisoned. Acquitted, he went to England where he became
prominent in politics and science. Invested with the title of
Count by the Holy Roman Empire, he chose Rumford for his title
after the name of the little New Hampshire town where he had
taught. He gave a large sum of money to Harvard College to found
the Rumford professorship of science.

eccentric: out of the centre.


A Liberal Education: from Science and Education; also published in
Lay Sermons, Addresses and Reviews.

Ichabod: cf. 1 Sam. iv, 21.

senior wranglership: in Cambridge University, England, one who has
attained the first class in the elementary division of the public
examination for honors in pure and mixed mathematics, commonly
called the mathematical tripos, those who compose the second rank
of honors being designated senior optimes, and those of the third
order junior optimes. The student taking absolutely the first
place in the mathematical tripos used to be called senior wrangler,
those following next in the same division being respectively termed
second, third, fourth, etc., wranglers. Century Dictionary.

double-first: any candidate for the degree of Bachelor of Arts in
Oxford University who takes first-class honors in both classics and
mathematics is said to have won a double-first.

Retzsch (1779-1857): a well-known German painter and engraver.

Test-Act: an English statute of 1673. It compelled all persons
holding office under the crown to take the oaths of supremacy and
of allegiance, to receive the sacrament according to the usage of
the Church of England, and to subscribe to the Declaration against

Poll: an abbreviation and transliteration of [Greek words], "the
mob"; university slang for the whole body of students taking merely
the degree of Bachelor of Arts, at Cambridge.

pluck: the rejection of a student, after examinations, who does not
come up to the standard.


On a Piece of Chalk: a lecture to working-men from Lay Sermons,
Addresses and Reviews.

Needles of the Isle of Wight: the needles are three white, pointed
rocks of chalk, resting on dark-colored bases, and rising abruptly
from the sea to a height of 100 feet. Baedeker's Great Britain.

Lulworth in Dorset, to Flamborough Head: Lulworth is on the
southern coast of England, west of the Isle of Wight: Flamborough
Head is on the northeastern coast of England and extends into the
German Ocean.

Weald: a name given to an oval-shaped chalk area in England,
beginning near the Straits of Dover, and extending into the
counties of Kent, Surrey, Hants, and Sussex.

Lieut. Brooke: Brooke devised an apparatus for deep-sea sounding
from which the weight necessary to sink the instrument rapidly, was
detached when it reached the bottom. The object was to relieve the
strain on the rope caused by rapid soundings. Improved apparatuses
have been invented since the time of Brooke.

Ehrenberg (1795-1876): a German naturalist noted for his studies of

Bailey of West Point (1811-1857): an American naturalist noted for
his researches in microscopy.

enterprise of laying down the telegraph-cable: the first Atlantic
telegraph-cable between England and America was laid in 1858 by
Cyrus W. Field of New York. Messages were sent over it for a few
weeks; then it ceased to act. A permanent cable was laid by Mr.
Field in 1866.

Dr. Wallich (1786-1854): a Danish botanist and member of the Royal

Mr. Sorby: President of the Geological Society of England, and
author of many papers on subjects connected with physical

Sir Charles Lyell (1797-1875): a British geologist, and one of the
first to uphold Darwin's Origin of Species.

Echinus: the sea-urchin; an animal which dwells in a spheroidal
shell built up from polygonal plates, and covered with sharp

Somme: a river of northern France which flows into the English
Channel northeast of Dieppe.

the chipped flints of Hoxne and Amiens: the rude instruments which
were made by primitive man were of chipped flint. Numerous
discoveries of large flint implements have been made in the north
of France, near Amiens, and in England. The first noted flint
implements were discovered in Hoxne, Suffolk, England, 1797. Cf.
Evans' Ancient Stone Implements and Lyell's Antiquity of Man.

Rev. Mr. Gunn (1800-1881): an English naturalist. Mr. Gunn sent
from Tasmania a large number of plants and animals now in the
British Museum.

"the whirligig of time": cf. Shakespeare, Twelfth Night, Act V, se.
I, l. 395.

Euphrates and Hiddekel: cf. Genesis ii, 14.

the great river, the river of Babylon: cf. Genesis xv, 18

Without haste, but without rest: from Goethe's Zahme Xenien. In a
letter to his sister, Huxley says: "And then perhaps by the
following of my favorite motto,--

"'Wie das Gestirn,
Ohne Hast,
Ohne Rast'--

something may be done, and some of Sister Lizzie's fond
imaginations turn out not altogether untrue." The quotation entire
is as follows:--

Wie das Gestirn,
Ohne Hast,
Aber ohne Rast,
Drehe sich jeder
Um die eigne Last.


The Principal Subjects of Education: an extract from the essay,
Science and Art in Relation to Education.

this discussion: "this" refers to the last sentence in the
preceding paragraph, in which Huxley says that it will be
impossible to determine the amount of time to be given to the
principal subjects of education until it is determined "what the
principal subjects of education ought to be."

Francis Bacon: cf. note [26].

the best chance of being happy: In connection with Huxley's work on
the London School Board, his biographer says that Huxley did not
regard "intellectual training only from the utilitarian point of
view; he insisted, e. g., on the value of reading for amusement as
one of the most valuable uses to hardworked people."

"Harmony in grey": cf. with l. 34 in Browning's Andrea del Sarto.

Hobbes (1588-1679): noted for his views of human nature and of
politics. According to Minto, "The merits ascribed to his style
are brevity, simplicity and precision."

Bishop Berkeley (1685-1753): an Irish prelate noted for his
philosophical writings and especially for his theory of vision
which was the foundation for modern investigations of the subject.
"His style has always been esteemed admirable; simple, felicitous
and sweetly melodious. His dialogues are sustained with great
skill." Minto's Manual of English Prose Literature.

We have been recently furnished with in prose: The Iliad of Homer
translated by Lang, Leaf and Myers, the first edition of which
appeared in 1882, is probably the one to which Huxley refers. The
Odyssey, translated by Butcher and Lang, appeared in 1879. Among
the best of the more recent translations of Homer are the Odyssey
by George Herbert Palmer; the Iliad by Arthur S. Way, and the
Odyssey by the same author.

Locke (1632-1704): an English philosopher of great influence. His
chief work is An Essay Concerning Human Understanding.

Franciscus Bacon sic cogitavit: thus Francis Bacon thought.


The Method of Scientific Investigation is an extract from the third
of six lectures given to workingmen on The Causes of the Phenomena
of Organic Nature in Darwiniana.

these terrible apparatus: apparatus is the form for both the
singular and plural; apparatuses is another form for the plural.

Incident in one of Moliere's plays: the allusion is to the hero,
M. Jourdain in the play, "La Bourgeois Gentilbomme."

these kind: modern writers regard kind as singular. Shakespeare
treated it as a plural noun, as "These kind of knaves I knew."

Newton: cf. [30].

Laplace (1749-1827): a celebrated French astronomer and
mathematician. He is best known for his theory of the formation of
the planetary systems, the so-called "nebular hypothesis." Until
recently this hypothesis has generally been accepted in its main
outlines. It is now being supplanted by the "Spiral Nebular
Hypothesis" developed by Professors Moulton and Chamberlin of the
University of Chicago. See Moulton's Introduction to Astronomy, p.


On the Physical Basis of Life: from Methods and Results; also
published in Lay Sermons, Addresses and Reviews. "The substance of
this paper was contained in a discourse which was delivered in
Edinburgh on the evening of Sunday, the 8th of November, 1868--
being the first of a series of Sunday evening addresses upon non-
theological topics, instituted by the Rev. J. Cranbrook. Some
phrases, which could possess only a transitory and local interest,
have been omitted; instead of the newspaper report of the
Archbishop of York's address, his Grace's subsequently published
pamphlet On the Limits of Philosophical inquiry is quoted, and I
have, here and there, endeavoured to express my meaning more fully
and clearly than I seem to have done in speaking--if I may judge by
sundry criticisms upon what I am supposed to have said, which have
appeared. But in substance, and, so far as my recollection serves,
in form, what is here written corresponds with what was there

Finner whale: a name given to a whale which has a dorsal fin. A
Finner whale commonly measures from 60 to 90 feet in length.

A fortiori: with stronger reason: still more conclusively.

well-known epigram: from Goethe's Venetianische Epigramme. The
following is a translation of the passage: Why do the people push
each other and shout? They want to work for their living, bring
forth children; and feed them as well as they possibly can. . . .
No man can attain to more, however much he may pretend to the

Maelstroms: a celebrated whirlpool or violent current in the Arctic
Ocean, near the western coast of Norway, between the islands of
Moskenaso and Mosken, formerly supposed to suck in and destroy
everything that approached it at any time, but now known not to be
dangerous except under certain conditions. Century Dictionary.
Cf. also Poe's Descent into the Maelstrom.

Milne-Edwards (1800-1885): a French naturalist. His Elements de
Zoologie won him a great reputation.

with such qualifications as arises: a typographical error.

De Bary (1831-1888): a German botanist noted especially for his
researches in cryptogamic botany.

No Man's Land: Huxley probably intends no specific geographical
reference. The expression is common as a designation of some
remote and unfrequented locality.

Kuhne (1837-1900): a German physiologist and professor of science
at Amsterdam and Heidelberg.

Debemur morti nos nostraque: Horace--Ars Poetica, line 63.

As forests change their foliage year by year,
Leaves, that come first, first tall and disappear;
So antique words die out, and in their room,
Others spring up, of vigorous growth and bloom;
Ourselves and all that's ours, to death are due,
And why should words not be mortal too?

Martin's translation.

peau de chagrin: skin of a wild ass.

Balzac (1799-1850): a celebrated French novelist of the realistic
school of fiction.

Barmecide feast: the allusion is to a story in the Arabian Nights
in which a member of the Barmecide family places a succession of
empty dishes before a beggar, pretending that they contain a rich

modus operandi: method of working.

Martinus Scriblerus: a reference to Memoirs of Martinus Scriblerus
written principally by John Arbuthnot, and published in 1741. The
purpose of the papers is given by Warburton and Spence in the
following extracts quoted from the Preface to the Memoirs of the
Extraordinary Life, Works and Discoveries of Martinus Scriblerus in
Elwin and Courthope's edition of Pope's works, vol. x, p. 273:--

"Mr. Pope, Dr. Arbuthnot, and Dr. Swift, in conjunction, formed the
project of a satire on the abuses of human learning; and to make it
better received, proposed to execute it in the manner of Cervantes
(the original author of this species of satire) under a continued
narrative of feigned adventures. They had observed that those
abuses still kept their ground against all that the ablest and
gravest authors could say to discredit them; they concluded,
therefore, the force of ridicule was wanting to quicken their
disgrace; and ridicule was here in its place, when the abuses had
been already detected by sober reasoning; and truth in no danger to
suffer by the premature use of so powerful an instrument."

"The design of this work, as stated by Pope himself, is to ridicule
all the false tastes in learning under the character of a man of
capacity enough, that had dipped into every art and science, but
injudiciously in each. It was begun by a club of some of the
greatest wits of the age--Lord Oxford, the Bishop of Rochester,
Pope, Congreve, Swift, Arbuthnot, and others. Gay often held the
pen; and Addison liked it very well, and was not disinclined to
come into it."

accounted for the operation of the meat-jack: from the paper "To
the learned inquisitor into nature, Martinus Scriblerus: the
society of free thinkers greeting." Elwin and Courthope, Pope's
works, vol. ?, p. 332.

The remainder of the essay endeavors to meet the charge of
materialism. The following is the conclusion:--

"In itself it is of little moment whether we express the phaenomena
of matter in terms of spirit; or the phaenomena of spirit in terms
of matter: matter may be regarded as a form of thought, thought may
be regarded as a property of matter--each statement has a certain
relative truth. But with a view to the progress of science, the
materialistic terminology is in every way to be preferred. For it
connects thought with the other phaenomena of the universe, and
suggests inquiry into the nature of those physical conditions, or
concomitants of thought, which are more or less accessible to us,
and a knowledge of which may, in future, help us to exercise the
same kind of control over the world of thought, as we already
possess in respect of the material world; whereas, the alternative,
or spiritualistic, terminology is utterly barren, and leads to
nothing but obscurity and confusion of ideas.

"Thus there can be little doubt, that the further science advances,
the more extensively and consistently will all the phaenomena of
Nature be represented by materialistic formulae and symbols. But
the man of science, who, forgetting the limits of philosophical
inquiry, slides from these formulae and symbols into what is
commonly understood by materialism, seems to me to place himself on
a level with the mathematician, who should mistake the x's and y's
with which he works his problems, for real entities--and with this
further disadvantage, as compared with the mathematician, that the
blunders of the latter are of no practical consequence, while the
errors of systematic materialism may paralyze the energies and
destroy the beauty of a life."


On Coral and Coral Reefs: from Critiques and Addresses. The essay
was published in 1870.

Sic et curalium: Thus also the coral, as soon as it touches the air
turns hard. It was a soft plant under the water.

Boccone (1633-1704): a noted Sicilian naturalist.

Marsigli (1658-1730): an Italian soldier and naturalist. He wrote
A Physical History of the Sea.

"Traite du Corail": "I made the coral bloom in vases full of sea-
water, and I noticed that what we believe to be the flower of this
so-called plant was in reality only an insect similar to a little
nettle or polype. I had the pleasure to see the paws or feet of
this nettle move, and having placed the vase full of water in which
the coral was, near the fire, at a moderate heat, all the little
insects expanded, the nettle stretched out its feet and formed what
M. de Marsigli and I had taken for the petals of the flower. The
calyx of this so-called flower is the very body of the animal
issued from its cell."

Reaumur (1683-1757): a French physiologist and naturalist, best
known as the inventor of the Reaumur thermometer. He was a member
of the French Academy of Science.

Bishop Wilson: Thomas Wilson (1663-1755), bishop of the Isle of
Man. Details of his life are given in the folio edition of his
works (1782). An appreciation of his religious writings is given
by Matthew Arnold in Culture and Anarchy. Bishop Wilson's words,
"To make reason and the will of God prevail," are the theme of
Arnold's essay, Sweetness and Light.

An eminent modern writer: Matthew Arnold (1822-1888), eldest son of
Thomas Arnold, headmaster of Rugby; a distinguished critic and
poet, and professor of poetry at Oxford. The allusion is to
Arnold's essay, Sweetness and Light. The phrase, "sweetness and
light," is one which Aesop uses in Swift's Battle of the Books to
sum up the superiority of the ancients over the moderns. "As for
us, the ancients, we are content, with the bee, to pretend to
nothing of our own beyond our wings and our voice, that is to say,
our flights and our language; for the rest, whatever we have got
has been by infinite labor and search, and ranging through every
corner of nature; the difference is, that instead of dirt and
poison we have rather chose to fill our hives with honey and wax,
thus furnishing mankind with the two noblest things, which are
sweetness and light." Arnold's purpose in the essay is to define
the cultured man as one who endeavors to make beauty and
intelligence prevail everywhere.

Abbe Trembley (1700-1784): a Swiss naturalist. He wrote "Memoires
pour servir a l'histoire d'un genre de polypes d'eau douce, a bras
en forme de cornes."

Bernard de Jussieu (1699-1776): a French botanist; founder of the
natural classification of plants. He was superintendent of the
Trianon Gardens.

Guettard (1715-1786): a French naturalist.

Monte Nuovo within the old crater of Somma: Monte Nuovo, a mountain
west of Naples; Somma, a mountain north of Vesuvius which with its
lofty, semicircular cliff encircles the active cone of Vesuvius.

Mauritius: an island in the Indian Ocean; Huxley visited the island
when on the voyage with the Rattlesnake. He wrote to his mother of
his visit: "This island is, you know, the scene of Saint Pierre's
beautiful story of Paul and Virginia, over which I suppose most
people have sentimentalized at one time or another of their lives.
Until we reached here I did not know that the tale was like the
lady's improver--a fiction founded on fact, and that Paul and
Virginia were at one time flesh and blood, and that their veritable
dust was buried at Pamplemousses in a spot considered as one of the
lions of the place, and visited as classic ground."

Mr. Darwin's coral reefs: The Structure and Distribution of Coral
Reefs, published in 1848.

Professor Jukes (1811-1869): an English geologist.

Mr. Dana (1813-1895): a well-known American geologist and
mineralogist; a professor at Yale from 1845. He wrote a number of
books among which is Coral and Coral Reefs.

Jurassic period: that part of the geological series which is older
than the Cretaceous and newer than the Triassic; so called from the
predominance of rocks of this age in the Jura Mountains. The three
great divisions of fossiliferous rocks are called the Triassic, the
Jurassic, and the Cretaceous.


The following reference books are suggested for a more complete
treatment of various points in the text:--

Andrews' History of England.
Green's Short History of the English People.
Traill's Social England.
Roger's A Student's History of Philosophy.
Royce's The Spirit of Modern Philosophy.
Huxley's Life and Letters.
Smalley's Mr. Huxley, in Scribner's Magazine for October, 1905.
Darwin's Life and Letters.

Book of the day: