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Inquiries into Human Faculty and Its Development by Francis Galton

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First issue of this Edition 1907


After some years had passed subsequent to the publication of this
book in 1883, its publishers, Messrs. Macmillan, informed me that
the demand for it just, but only just warranted a revised issue. I
shrank from the great trouble of bringing it up to date because it,
or rather many of my memoirs out of which it was built up, had
become starting-points for elaborate investigations both in England
and in America, to which it would be difficult and very laborious to
do justice in a brief compass. So the question of a Second Edition
was then entirely dropped. Since that time the book has by no means
ceased to live, for it continues to be quoted from and sought for,
but is obtainable only with difficulty, and at much more than its
original cost, at sales of second-hand books. Moreover, it became
the starting point of that recent movement in favour of National
Eugenics (see note p. 24 in first edition) which is recognised by
the University of London, and has its home in University College.

Having received a proposal to republish the book in its present
convenient and inexpensive form, I gladly accepted it, having first
sought and received an obliging assurance from Messrs. Macmillan
that they would waive all their claims to the contrary in my favour.

The following small changes are made in this edition. The
illustrations are for the most part reduced in size to suit the
smaller form of the volume, the lettering of the composites is
rearranged, and the coloured illustration is reproduced as closely
as circumstances permit. Two chapters are omitted, on "Theocratic
Intervention" and on the "Objective Efficacy of Prayer." The earlier
part of the latter was too much abbreviated from the original memoir
in the _Fortnightly Review_, 1872, and gives, as I now perceive, a
somewhat inexact impression of its object, which was to investigate
certain views then thought orthodox, but which are growing obsolete.
I could not reinsert these omissions now with advantage, unless
considerable additions were made to the references, thus giving more
appearance of personal controversy to the memoirs than is desirable.
After all, the omission of these two chapters, in which I find
nothing to recant, improves, as I am told, the general balance of the


The Teletype: a printing Electric Telegraph, 1850;
The Narrative of an Explorer in Tropical South Africa, 1853,
in "Minerva Library of Famous Books," 1889;
Notes on Modern Geography (Cambridge Essays, 1855, etc.);
Arts of Campaigning: an Inaugural Lecture delivered at Aldershot, 1855;
The Art of Travel, or Shifts and Contrivances available in Wild Countries,
1855, 1856, 1860 (1859);
fourth edition, recast and enlarged, 1867, 1872;
Vacation Tourists and Notes on Travel, 1861, 1862, 1864;
Meteorographica, or Methods of Mapping the Weather, 1863;
Hereditary Genius: an Enquiry into its Laws and Consequences, 1869;
English Men of Science: their Nature and Nurture, 1874;
Address to the Anthropological Departments of the British Association
(Plymouth, 1877);
Generic Images: with Autotype Illustrations
(from the Proceedings of the Royal Institution), 1879;
Inquiries into Human Faculty and its Development, 1883;
Record of Family Faculties, 1884; Natural Inheritance, 1889;
Finger-Prints, 1892;
Decipherments of Blurred Finger-Prints
(supplementary chapters to former work), 1893;
Finger-Print Directories, 1895;
Introduction to Life of W. Cotton Oswell, 1900;
Index to Achievements of Near Kinsfolk
of some of the Fellows of the Royal Society, 1904;
Eugenics: its Definition, Scope, and Aims
(Sociological Society Papers, vols. I. and II.), 1905;
Noteworthy Families (Modern Science);
And many papers in the Proceedings of the Royal Society,
Journals of the Geographical Society and the Anthropological Institute,
the Reports of the British Association, the Philosophical Magazine,
and Nature.

Galton also edited:
Hints to Travellers, 1878;
Life-History Album (British Medical Association), 1884,
second edition, 1902;
Biometrika (edited in consultation with F.G. and W.F.R. Weldon), 1901,
and under his direction was designed a
Descriptive List of Anthropometric Apparatus, etc., 1887.


The following Memoirs by the author have been freely made use of in
the following pages:--

1863: The First Steps towards the Domestication of Animals
(_Journal of Ethnological Society_);
1871: Gregariousness in Cattle and in Men
(_Macmillan's Magazine_);
1872: Statistical Inquiries into the Efficacy of Prayer
(_Fortnightly Review_);
1873: Relative Supplies from Town and Country Families
to the Population of Future Generations
(_Journal of Statistical Society_);
Hereditary Improvement (_Fraser's Magazine_);
Africa for the Chinese (_Times_, June 6);
1875: Statistics by Intercomparison (_Philosophical Magazine_);
Twins, as a Criterion of the Relative Power of Nature and Nurture
(_Fraser's Magazine_, and
_Journal of Anthropological Institute_);
1876: Whistles for Determining the Upper Limits of Audible Sound
(_S. Kensington Conferences_, in connection with the
Loan Exhibition of Scientific Instruments, p. 61);
1877: Presidential Address to the Anthropological Department
of the British Association at Plymouth
(_Report of British Association_);
1878: Composite Portraits (_Nature_, May 23, and
_Journal of Anthropological Institute_);
1879: Psychometric Experiments (_Nineteenth Century_,
and _Brain_, part vi.);
Generic Images (_Nineteenth Century; Proceedings of
Royal Institution_, with plates);
Geometric Mean in Vital and Social Statistics (_Proceedings
of Royal Society_);
1880: Visualised Numerals (_Nature_, Jan. 15 and March 25, and
_Journal of Anthropological Institute_);
Mental Imagery (_Fortnightly Review; Mind_);
1881: Visions of Sane Persons (_Fortnightly Review_, and
_Proceedings of Royal Institution_);
Composite Portraiture (_Journal of Photographical Society
of Great Britain_, June 24);
1882: Physiognomy of Phthisis (_Guy's Hospital Reports_, vol. xxv.);
Photographic Chronicles from Childhood to Age (_Fortnightly Review_);
The Anthropometric Laboratory (_Fortnightly Review_);
1883: Some Apparatus for Testing the Delicacy of the Muscular
and other Senses (_Journal of Anthropological Institute_,
1883, etc.).

_Memoirs in Eugenics_.

1901: Huxley Lecture, Anthropological Institute (_Nature,_ Nov. 1901);
Smithsonian Report for 1901 (_Washington_, p. 523);
1904: Eugenics, its Definition, Scope and Aims
(Sociological Paper, vol. i., _Sociological Institute_);
1905: Restrictions in Marriage, Studies in National Eugenics,
Eugenics as a Factor in Religion (Sociological Papers, vol. ii.);
1907: Herbert Spencer Lecture, University of Oxford,
on Probability the Foundation of Eugenics.

The following books by the author have been referred or alluded to
in the following pages:--

1853: Narrative of an Explorer in Tropical South-Western Africa
1854: Art of Travel (several subsequent editions,
the last in 1872, _Murray_);
1869: Hereditary Genius, its Laws and Consequences
1874: English Men of Science, their Nature and their Nurture




Origin and object of book.


Many varieties may each be good of its kind; advantage
of variety; some peculiarities are, however, harmful.


Large number of elements in the human expression; of
touches in a portrait; difficulty of measuring the separate
features; or of selecting typical individuals; the typical
English face; its change at different historical periods;
colour of hair of modern English; caricatures.


(See Appendix for three Memoirs describing successive
stages of the method).--Object and principle of the process;
description of the plate--composites of medals; of family
portraits; of the two sexes and of various ages; of Royal
Engineers; the latter gives a clue to one direction in which
the English race might be improved; of criminals; of the
consumptive; ethnological application of the process.


Anthropometric Committee; statistical anomalies in stature
as dependent on age; town and rural population; athletic
feats now and formerly; increase of stature of middle classes;
large number of weakly persons; some appearances of weakness
may be fallacious; a barrel and a wheel; definition
of word "eugenic."


It is the attribute of high races; useful stimuli to activity;
fleas, etc.; the preservation of the weakly as exercises for
pity; that of foxes for sport.


Sensation and pain; range and grades of sensation;
idiots; men and women; the blind; reading by touch;
sailors; paucity of words to express gradation.


(See also Appendix, p. 248).--Geometric series of
weights; method of using them; the same principle is
applicable to other senses; the tests only measure the state
of faculties at time of trial; cautions in constructing the
test weights; multiplicity of the usual perceptions.


(See also Appendix, p. 252).--Construction of them; loss
of power of hearing high notes as age advances; trials upon
animals; sensitivity of cats to high notes; of small dogs and


Want of anthropometric laboratories; of family records;
opportunities in schools; Admiralty records of life of each
seaman; family registers (see also 220); autotypes; medical
value of ancestral life-histories (see also 220); of their
importance to human eugenics.


Colour blindness usually unsuspected; unconsciousness of
high intellectual gifts; of peculiarities of mental imagery;
heredity of colour blindness in Quakers; Young and Dalton.


Objects of statistical science; constancy and continuity
of statistical results; groups and sub-groups; augival or
ogival curves; wide application of the ogival; method;
example; first method of comparing two ogival groups;
centesimal grades; example; second method of comparing
ogival groups; statistical records easily made with a


Caprice and coyness of females; its cause; observations
of character at schools; varieties of likings and antipathies;
horror of snakes is by no means universal; the horror of
blood among cattle is variable.


Peculiarities of criminal character; some of them are
normal and not morbid; their inheritance as in the Jukes
family; epileptics and their nervous instability; insanity;
religious rapture; strange views of the insane on individuality;
their moody segregation; the religious discipline of
celibacy, fasting and solitude (see also 125); large field of
study among the insane and idiotic.


Most men shrink from responsibility; study of gregarious
animals: especially of the cattle of the Damaras; fore-oxen
to waggon teams; conditions of safety of herds; cow and
young calf when approached by lions; the most effective
size of herd; corresponding production of leaders; similarly
as regards barbarian tribes and their leaders; power of
tyranny vested in chiefs; political and religious persecutions;
hence human servility; but society may flourish without
servility; its corporate actions would then have statistical
constancy; nations who are guided by successive orators,
etc., must be inconstant; the romantic side of servility; free
political life.


Reference to _Hereditary Genius_.


Purport of inquiry; circular of questions (see Appendix
for this); the first answers were from scientific men,
and were negative; those from persons in general society
were quite the reverse; sources of my materials; they are
mutually corroborative. Analysis of returns from 100
persons mostly of some eminence; extracts from replies of
those in whom the visualising faculty is highest; those in
whom it is mediocre; lowest; conformity between these
and other sets of haphazard returns; octile, median, etc.,
values; visualisation of colour; some liability to exaggeration;
blindfold chess-players; remarkable instances of visualisation;
the faculty is not necessarily connected with keen sight or
tendency to dream; comprehensive imagery; the faculty in different
sexes and ages; is strongly hereditary; seems notable among
the French; Bushmen; Eskimo; prehistoric men; admits of being
educated; imagery usually fails in flexibility; special and generic
images (see also Appendix); use of the faculty.


General account of the peculiarity; mutually corroborative
statements; personal evidence given at the Anthropological
Institute; specimens of a few descriptions and
illustrative woodcuts; great variety in the Forms; their
early origin; directions in which they run; bold conceptions
of children concerning height and depth; historical
dates, months, etc.; alphabet; derivation of the Forms
from the spoken names of numerals; fixity of the Form
compared to that of the handwriting; of animals working
in constant patterns; of track of eye when searching for
lost objects; occasional origin from figures on clock; from
various other sources; the non-decimal nomenclature of
numerals; perplexity caused by it. Description of figures
in Plate I.; Plate II.; Plate III.; Plate IV. Colours
assigned to numerals (see 105); personal characters; sex;
frequency with which the various numerals are used in the


(Description of Plate IV. continued) Associations with
numerals; with words and letters; illustrations by Dr. J.
Key; the scheme of one seer unintelligible to other seers;
mental music, etc.


Sane persons often see visions; the simpler kinds of
visions; unconsciousness of seers, at first, of their
peculiarity; subsequent dislike to speak about it; imagery
connected with words; that of Mrs. Haweis; automatic changes
in dark field of eye; my own experiences; those of Rev. G. Henslow;
visions frequently unlike vivid visualisations; phantasmagoria;
hallucinations; simile of a seal in a pond; dreams and partial
sensitiveness of brain; hallucinations and illusions, their causes;
"faces in the fire," etc.; sub-conscious picture-drawing; visions
based on patched recollections; on blended recollections; hereditary
seership; visions caused by fasting, etc.; by spiritual discipline
(see also 47); star of Napoleon I.; hallucinations of
great men; seers commoner at some periods than at others;
reasons why.


Their effects are difficult to separate; the same character
has many phases; Renaissance; changes owing merely to
love of change; feminine fashions; periodical sequences of
changed character in birds; the interaction of nurture and


Derived from experience; especially from childish recollections
(see 141); abstract ideas; cumulative ideas, like composite
portraits (see also Appendix, "Generic Images," p. 229);
their resemblance even in details.


Difficulty of watching the mind in operation; how it may
be overcome; irksomeness of the process; tentative experiments;
method used subsequently; the number of recurrent
associations; memory; ages at which associations are
formed; similarity of the associations in persons of the same
country and class of society; different descriptions of
classified; their relative frequency; abstract ideas are
slowly formed; multifariousness of sub-conscious operations.


Act of thinking analysed; automatic mental work; fluency
of words and of imagery; processes of literary composition;
fluency of spiritual ideas; visionary races of men; morbid
ideas of inspiration (see Enthusiasm).


Accidents of education, religion, country, etc.; deaf-mutes
and religious ritual; religion in its essentials; all religious
teachers preach faith and instil prejudices; origin of the
faculty of conscience; evolution is always behindhand;
good men of various faiths; the fear of death; terror is
easily taught; gregarious animals (see also 47); suspiciousness
in the children of criminals; Dante and contemporary
artists on the terrors of hell; aversion is easily taught,
Eastern ideas of clean and unclean acts; the foregoing
influences affect entire classes.


It supplies means of comparing the effects of nurture and
nature; physiological signification of twinship; replies to
a circular of inquiries; eighty cases of close resemblance
between twins; the points in which their resemblance was
closest; extracts from the replies; interchangeableness of
likeness; cases of similar forms of insanity in both twins;
their tastes and dispositions; causes of growing dissimilarity
mainly referred to illness; partly to gradual development of
latent elements of dissimilarity; effect of childish illnesses
in permanently checking growth of head; parallel lives and
deaths among twins; necessitarianism; twenty cases of great
dissimilarity; extracts from the replies; evidence of slight
exaggeration; education is almost powerless to diminish
natural difference of character; simile of sticks floating
down a brook; depth of impressions made in childhood;
they are partly due to the ease with which parents and
children understand one another; cuckoos forget the teachings
of their foster-mothers.


Alternative hypotheses of the prehistoric process of
domestication; savages rear captive animals; instances in
North America; South America; North Africa; Equatorial
Africa; South Africa; Australia; New Guinea Group;
Polynesia; ancient Syria. Sacred animals; menageries
and shows in amphitheatres; instances in ancient Egypt;
Assyria; Rome; Mexico; Peru; Syria and Greece.
Domestication is only possible when the species has certain
natural faculties, viz.--great hardiness; fondness for man;
desire of comfort; usefulness to man; fertility; being easy
to tend. Habitual selection of the tamest to breed from.
Exceptions; summary.


Steady improvement in the birthright of successive generations;
our ignorance of the origin and purport of all existence;
of the outcome of life on this earth; of the conditions
of consciousness; slow progress of evolution and its
system of ruthless routine; man is the heir of long bygone
ages; has great power in expediting the course of evolution;
he might render its progress less slow and painful;
does not yet understand that it may be his part to do so.


Difference between the best specimens of a poor race and
the mediocre ones of a high race; typical centres to which
races tend to revert; delicacy of highly-bred animals; their
diminished fertility; the misery of rigorous selection; it is
preferable to replace poor races by better ones; strains of
emigrant blood; of exiles.


Conquest, migrations, etc.; sentiment against extinguishing
races; is partly unreasonable; the so-called "aborigines";
on the variety and number of different races
inhabiting the same country; as in Spain; history of the
Moors; Gypsies; the races in Damara Land; their recent
changes; races in Siberia; Africa; America; West Indies;
Australia and New Zealand; wide diffusion of Arabs and
Chinese; power of man to shape future humanity.


Over-population; Malthus--the danger of applying his
prudential check; his originality; his phrase of misery check
is in many cases too severe; decaying races and the cause
of decay.


Estimate of their relative effects on a population in a few
generations; example.


On the demand for definite proposals how to improve
race; the demand is not quite fair, and the reasons why;
nevertheless attempt is made to suggest the outline of one;
on the signs of superior race; importance of giving weight
to them when making selections from candidates who are
personally equal; on families that have thriven; that are
healthy and long-lived; present rarity of our knowledge
concerning family antecedents; Mr. F.M. Hollond on the
superior morality of members of large families; Sir William
Gull on their superior vigour; claim for importance of
further inquiries into the family antecedents of those who
succeed in after life; probable large effect of any system
by which marks might be conferred on the ground of family


These have frequently been made in order to furnish
marriage portions; they, as well as the adoption of gifted
children of gifted families, may hereafter become common;
college statutes enjoining celibacy on Fellows; reverse effect
to that for which prizes at races were established; the recent
reform of those statutes and numerous marriages in consequence;
the English race has yet to be explored for its
natural wealth; those who are naturally gifted would be
disinclined to squander their patrimony; social consideration;
honest pride in goodness of race.


Epitome of data; the apparent place of man in nature;
he should look upon himself as a freeman; he should assist
in furthering evolution; his present ability to do so; the
certainty that his ability of doing so will increase; importance
of life-histories; brief summary.



I. Extract of Memoir read in 1878 before the Anthropological
II. Generic Images, extract from Lecture in 1879 to Royal
III. Memoir read in 1881 before the Photographic Society.


Memoir read in 1873 before the Statistical Society.


Memoir read in 1882 before the Anthropological Institute.


Read in 1876 at the South Kensington Conferences in
connection with the Loan Exhibition of Scientific Instruments.


Circulated in 1880.









Since the publication of my work on _Hereditary Genius_ in 1869, I
have written numerous memoirs, of which a list is given in an
earlier page, and which are scattered in various publications. They
may have appeared desultory when read in the order in which they
appeared, but as they had an underlying connection it seems worth
while to bring their substance together in logical sequence into a
single volume. I have revised, condensed, largely re-written,
transposed old matter, and interpolated much that is new; but traces
of the fragmentary origin of the work still remain, and I do not
regret them. They serve to show that the book is intended to be
suggestive, and renounces all claim to be encyclopedic. I have indeed,
with that object, avoided going into details in not a few cases
where I should otherwise have written with fulness, especially in
the Anthropometric part. My general object has been to take note of
the varied hereditary faculties of different men, and of the great
differences in different families and races, to learn how far
history may have shown the practicability of supplanting inefficient
human stock by better strains, and to consider whether it might not
be our duty to do so by such efforts as may be reasonable, thus
exerting ourselves to further the ends of evolution more rapidly and
with less distress than if events were left to their own course. The
subject is, however, so entangled with collateral considerations
that a straightforward step-by-step inquiry did not seem to be the
most suitable course. I thought it safer to proceed like the
surveyor of a new country, and endeavour to fix in the first
instance as truly as I could the position of several cardinal points.
The general outline of the results to which I finally arrived became
more coherent and clear as this process went on; they are brieflv
summarised in the concluding chapter.


We must free our minds of a great deal of prejudice before we can
rightly judge of the direction in which different races need to be
improved. We must be on our guard against taking our own instincts
of what is best and most seemly, as a criterion for the rest of
mankind. The instincts and faculties of different men and races
differ in a variety of ways almost as profoundly as those of animals
in different cages of the Zoological Gardens; and however diverse and
antagonistic they are, each may be good of its kind. It is obviously
so in brutes; the monkey may have a horror at the sight of a snake,
and a repugnance to its ways, but a snake is just as perfect an
animal as a monkey. The living world does not consist of a
repetition of similar elements, but of an endless variety of them,
that have grown, body and soul, through selective influences into
close adaptation to their contemporaries, and to the physical
circumstances of the localities they inhabit. The moral and
intellectual wealth of a nation largely consists in the multifarious
variety of the gifts of the men who compose it, and it would be the
very reverse of improvement to make all its members assimilate to a
common type. However, in every race of domesticated animals, and
especially in the rapidly-changing race of man, there are elements,
some ancestral and others the result of degeneration, that are of
little or no value, or are positively harmful. We may, of course, be
mistaken about some few of these, and shall find in our fuller
knowledge that they subserve the public good in some indirect manner;
but, notwithstanding this possibility, we are justified in roundly
asserting that the natural characteristics of every human race admit
of large improvement in many directions easy to specify.

I do not, however, offer a list of these, but shall confine myself
to directing attention to a very few hereditary characteristics of a
marked kind, some of which are most desirable and others greatly the
reverse; I shall also describe new methods of appraising and
defining them. Later on in the book I shall endeavour to define the
place and duty of man in the furtherance of the great scheme of
evolution, and I shall show that he has already not only adapted
circumstance to race, but also, in some degree and often
unconsciously, race to circumstance; and that his unused powers in
the latter direction are more considerable than might have been

It is with the innate moral and intellectual faculties that the book
is chiefly concerned, but they are so closely bound up with the
physical ones that these must be considered as well. It is, moreover,
convenient to take them the first, so I will begin with the features.


The differences in human features must be reckoned great, inasmuch
as they enable us to distinguish a single known face among those of
thousands of strangers, though they are mostly too minute for
measurement. At the same time, they are exceedingly numerous. The
general expression of a face is the sum of a multitude of small
details, which are viewed in such rapid succession that we seem to
perceive them all at a single glance. If any one of them disagrees
with the recollected traits of a known face, the eye is quick at
observing it, and it dwells upon the difference. One small
discordance overweighs a multitude of similarities and suggests a
general unlikeness; just as a single syllable in a sentence
pronounced with a foreign accent makes one cease to look upon the
speaker as a countryman. If the first rough sketch of a portrait be
correct so far as it goes, it may be pronounced an excellent likeness;
but a rough sketch does not go far; it contains but few traits for
comparison with the original. It is a suggestion, not a likeness; it
must be coloured and shaded with many touches before it can really
resemble the face, and whilst this is being done the maintenance of
the likeness is imperilled at every step. I lately watched an able
artist painting a portrait, and endeavoured to estimate the number
of strokes with his brush, every one of which was thoughtfully and
firmly given. During fifteen sittings of three working hours
each--that is to say, during forty-five hours, or two thousand four
hundred minutes--he worked at the average rate of ten strokes of the
brush per minute. There were, therefore, twenty-four thousand
separate traits in the completed portrait, and in his opinion some,
I do not say equal, but comparably large number of units of
resemblance with the original.

The physiognomical difference between different men being so
numerous and small, it is impossible to measure and compare them
each to each, and to discover by ordinary statistical methods the
true physiognomy of a race. The usual way is to select individuals
who are judged to be representatives of the prevalent type, and to
photograph them; but this method is not trustworthy, because the
judgment itself is fallacious. It is swayed by exceptional and
grotesque features more than by ordinary ones, and the portraits
supposed to be typical are likely to be caricatures. One fine Sunday
afternoon I sat with a friend by the walk in Kensington Gardens that
leads to the bridge, and which on such occasions is thronged by
promenaders. It was agreed between us that whichever first caught
sight of a typical John Bull should call the attention of the other.
We sat and watched keenly for many minutes, but neither of us found
occasion to utter a word.

The prevalent type of English face has greatly changed at different
periods, for after making large allowance for the fashion in
portrait painting of the day, there remains a great difference
between the proportion in which certain casts of features are to be
met with at different dates. I have spent some time in studying the
photographs of the various portraits of English worthies that have
been exhibited at successive loan collections, or which are now in
the National Portrait Gallery, and have traced what appear to be
indisputable signs of one predominant type of face supplanting
another. For instance, the features of the men painted by and about
the time of Holbein have usually high cheekbones, long upper lips,
thin eyebrows, and lank dark hair. It would be impossible, I think,
for the majority of modern Englishmen so to dress themselves and
clip and arrange their hair, as to look like the majority of these

Englishmen are now a fair and reddish race, as may be seen from the
Diagram, taken from the Report of the Anthropometric Committee to
the British Association in 1880 and which gives the proportion in
which the various colours of hair are found among our professional

[Illustration: ]

I take the professional classes because they correspond with the
class of English worthies better than any of the others from which
returns have been collected. The Diagram, however, gives a fair
representation of other classes of the community. For instance, I
have analysed the official records of the very carefully-selected
crews of H.M. S. _Alert_ and _Discovery_ in the Arctic Expedition of
1875-6, and find the proportion of various shades of hair to be the
same among them as is shown in the Diagram. Seven-tenths of the
crews had complexions described as light, fair, fresh, ruddy or
freckled, and the same proportion had blue or gray eyes. They would
have contrasted strongly with Cromwell's regiment of Ironsides, who
were recruited from the dark-haired men of the fen districts, and
who are said to have left the impression on contemporary observers
as being men of a peculiar breed. They would also probably have
contrasted with any body of thoroughgoing Puritan soldiers taken at
haphazard; for there is a prevalence of dark hair among men of
atrabilious and sour temperament.

If we may believe caricaturists, the fleshiness and obesity of many
English men and women in the earlier years of this century must have
been prodigious. It testifies to the grosser conditions of life in
those days, and makes it improbable that the types best adapted to
prevail then would be the best adapted to prevail now.


As a means of getting over the difficulty of procuring really
representative faces, I contrived the method of composite portraiture,
which has been explained of late on many occasions, and of which a
full account will be found in Appendix A. The principle on which the
composites are made will best be understood by a description of my
earlier and now discarded method; it was this--(1) I collected
photographic portraits of different persons, all of whom had been
photographed in the same aspect (say full face), and under the same
conditions of light and shade (say with the light coming from the
right side). (2) I reduced their portraits photographically to the
same size, being guided as to scale by the distance between any two
convenient points of reference in the features; for example, by the
vertical distance between two parallel lines, one of which passed
through the middle of the pupils of the eyes and the other between
the lips. (3) I superimposed the portraits like the successive
leaves of a book, so that the features of each portrait lay as
exactly as the case admitted, in front of those of the one behind it,
eye in front of eye and mouth in front of mouth. This I did by
holding them successively to the light and adjusting them, then by
fastening each to the preceding one with a strip of gummed paper
along one of the edges. Thus I obtained a book, each page of which
contained a separate portrait, and all the portraits lay exactly in
front of one another. (4) I fastened the book against the wall in
such a way that I could turn over the pages in succession, leaving
in turn each portrait flat and fully exposed. (5) I focused my
camera on the book fixed it firmly, and put a sensitive plate inside
it. (6) I began photographing, taking one page after the other in
succession without moving the camera, but putting on the cap whilst I
was turning over the pages, so that an image of each of the
portraits in succession was thrown on the same part of the
sensitised plate.

Only a fraction of the exposure required to make a good picture was
allowed to each portrait. Suppose that period was twenty seconds,
and that there were ten portraits, then an exposure of two seconds
would be allowed for each portrait, making twenty seconds in all.
This is the principle of the process, the details of that which I
now use are different and complex. They are fully explained in the
Appendix for the use of those who may care to know about them.

The effect of composite portraiture is to bring into evidence all
the traits in which there is agreement, and to leave but a ghost of
a trace of individual peculiarities. There are so many traits in
common in all faces that the composite picture when made from many
components is far from being a blur; it has altogether the look of
an ideal composition.

It may be worth mentioning that when I take any small bundle of
portraits, selected at hazard, I have generally found it easy to
sort them into about five groups, four of which have enough
resemblance among themselves to make as many fairly clear composites,
while the fifth consists of faces that are too incongruous to be
grouped in a single class. In dealing with portraits of brothers and
sisters, I can generally throw most of them into a single group, with

In the small collection of composites given in the Plate facing p. 8,
I have purposely selected many of those that I have previously
published, and whose originals, on a larger scale, I have at various
times exhibited, together with their components, in order to put the
genuineness of the results beyond doubt. Those who see them for the
first time can hardly believe but that one dominant face has
overpowered the rest, and that they are composites only in name. When,
however, the details are examined, this objection disappears. It is
true that with careless photography one face may be allowed to
dominate, but with the care that ought to be taken, and with the
precautions described in the Appendix, that does not occur. I have
often been amused when showing composites and their components to
friends, to hear a strong expression of opinion that the
predominance of one face was evident, and then on asking which face
it was, to discover that they disagreed. I have even known a
composite in which one portrait seemed unduly to prevail, to be
remade without the component in question, and the result to be much
the same as before, showing that the reason of the resemblance was
that the rejected portrait had a close approximation to the ideal
average picture of the rest.

These small composites give a better notion of the utmost capacity
of the process than the larger ones, from which they are reduced.
In the latter, the ghosts of individual peculiarities are more
visible, and usually the equal traces left by every member of a
moderately-sized group can be made out by careful inspection; but it
is hardly possible to do this in the pictures in the Plate, except
in a good light and in a very few of the cases. On the other hand,
the larger pictures do not contain more detail of value than the
smaller ones.


The medallion of Alexander the Great was made by combining the
images of six different medals, with a view of obtaining the type of
features that the makers of those medals concurred in desiring to
ascribe to him. The originals were kindly selected for me by Mr. R.
Stuart Poole from the collection in the British Museum. This
composite was one of the first I ever made, and is printed together
with its six components in the _Journal of the Royal Institution_,
in illustration of a lecture I gave there in April 1879. It seems to
me that it is possible on this principle to obtain a truer likeness
of a man than in any other way. Every artist makes mistakes; but by
combining the conscientious works of many artists, their separate
mistakes disappear, and what is common to all of their works remains.
So as regards different photographs of the same person, those
accidental momentary expressions are got rid of, which an ordinary
photograph made by a brief exposure cannot help recording. On the
other hand, any happy sudden trait of expression is lost. The
composite gives the features in repose.

The next pair of composites (full face and profile) on the Plate has
not been published before. The interest of the pair lies chiefly in
their having been made from only two components, and they show how
curiously even two faces that have a moderate family likeness will
blend into a single one. That neither of these predominated in the
present case will be learned from the following letter by the father
of the ladies, who is himself a photographer:--

"I am exceedingly obliged for the very curious and interesting
composite portraits of my two children. Knowing the faces so well,
it caused me quite a surprise when I opened your letter. I put one
of the full faces on the table for the mother to pick up casually.
She said, 'When did you do this portrait of A? how _like_ she is to B!
Or _is_ it B? I never thought they were so like before.' It has
puzzled several people to say whether the profile was intended for A
or B. Then I tried one of them on a friend who has not seen the
girls for years. He said, 'Well, it is one of the family for certain,
but I don't know which.'"

[Illustration: ]

I have made several other family portraits, which to my eye seem
great successes, but must candidly own that the persons whose
portraits are blended together seldom seem to care much for the
result, except as a curiosity. We are all inclined to assert our
individuality, and to stand on our own basis, and to object to being
mixed up indiscriminately with others. The same feeling finds
expression when the resident in a suburban street insists on calling
his house a villa with some fantastic name, and refuses, so long as
he can, to call it simply Number so and so in the street.

The last picture in the upper row shows the easy way in which young
and old, male and female, combine to form an effective picture. The
components consist in this case of the father and mother, two sons,
and two daughters. I exhibited the original of this, together with
the portraits from which it was taken, at the Loan Photographic
Exhibition at the Society of Arts in February 1882. I also sent
copies of the original of this same composite to several amateur
photographers, with a circular letter asking them to get from me
family groups for the purpose of experiments, to see how far the
process was suitable for family portraiture.

The middle row of portraits illustrates health, disease, and
criminality. For health, I have combined the portraits of twelve
officers of the Royal Engineers with about an equal number of
privates, which were taken for me by Lieutenant Darwin, R.E. The
individuals from whom this composite was made, which has not come
out as clearly as I should have liked, differed considerably in
feature, and they came from various parts of England. The points they
had in common were the bodily and mental qualifications required for
admission into their select corps, and their generally British
descent. The result is a composite having an expression of
considerable vigour, resolution, intelligence, and frankness. I have
exhibited both this and others that were made respectively from the
officers, from the whole collection of privates--thirty-six in
number--and from that selected portion of them that is utilised in
the present instance.

This face and the qualities it connotes probably gives a clue to the
direction in which the stock of the English race might most easily
be improved. It is the essential notion of a race that there should
be some ideal typical form from which the individuals may deviate in
all directions, but about which they chiefly cluster, and towards
which their descendants will continue to cluster. The easiest
direction in which a race can be improved is towards that central
type, because nothing new has to be sought out. It is only necessary
to encourage as far as practicable the breed of those who conform
most nearly to the central type, and to restrain as far as may be
the breed of those who deviate widely from it. Now there can hardly
be a more appropriate method of discovering the central
physiognomical type of any race or group than that of composite

As a contrast to the composite of the Royal Engineers, I give those
of two of the coarse and low types of face found among the criminal
classes. The photographs from which they were made are taken from
two large groups. One are those of men undergoing severe sentences
for murder and other crimes connected with violence; the other of
thieves. They were reprints from those taken by order of the prison
authorities for purposes of identification. I was allowed to obtain
copies for use in my inquiries by the kind permission of Sir Edmund
Du Cane, H.M. Director of Prisons. The originals of these and their
components have frequently been exhibited. It is unhappily a fact
that fairly distinct types of criminals breeding true to their kind
have become established, and are one of the saddest disfigurements
of modern civilisation. To this subject I shall recur.

I have made numerous composites of various groups of convicts, which
are interesting negatively rather than positively. They produce
faces of a mean description, with no villainy written on them. The
individual faces are villainous enough, but they are villainous in
different ways, and when they are combined, the individual
peculiarities disappear, and the common humanity of a low type is all
that is left.

The remaining portraits are illustrations of the application of the
process to the study of the physiognomy of disease. They were
published a year ago with many others, together with several of
the portraits from which they were derived, in a joint memoir by
Dr. Mahomed and myself, in vol. xxv. of the _Guy's Hospital Reports_.
The originals and all the components have been exhibited on several

In the lower division of the Plate will be found three composites,
each made from a large number of faces, unselected, except on the
ground of the disease under which they were suffering. When only few
portraits are used, there must be some moderate resemblance between
them, or the result would be blurred; but here, dealing with as many
as 56, 100, and 50 cases respectively, the combination of any medley
group results in an ideal expression.

It will be observed that the composite of 56 female faces is made by
the blending of two other composites, both of which are given. The
history was this--I took the 56 portraits and sorted them into two
groups; in the first of these were 20 portraits that showed a
tendency to thin features, in the other group there were 36 that
showed a tendency to thickened features. I made composites of each
of them as shown in the Plate. Now it will be remarked that,
notwithstanding the attempt to make two contrasted groups, the
number of mediocre cases was so great that the composities of the
two groups are much alike. If I had divided the 56 into two
haphazard groups, the results would have been closely alike, as I
know from abundant experience of the kind. The co-composite of the
two will be observed to have an intermediate expression. The test
and measure of statistical truth lies in the degree of accordance
between results obtained from different batches of instances of the
same generic class. It will be gathered from these instances that
composite portraiture may attain statistical constancy, within
limits not easily distinguished by the eye, after some 30 haphazard
portraits of the same class have been combined. This at least has
been my experience thus far.

The two faces illustrative of the same type of tubercular disease
are very striking; the uppermost is photographically interesting as
a case of predominance of one peculiarity, happily of no harm to the
effect of the ideal wan face. It is that one of the patients had a
sharply-checked black and white scarf, whose pattern has asserted
itself unduly in the composite. In such cases I ought to throw the
too clearly defined picture a little out of focus. The way in which
the varying brightness of different pictures is reduced to a uniform
standard of illumination is described in the Appendix.

It must be clearly understood that these portraits do not profess to
give the whole story of the physiognomy of phthisis. I have not room
to give illustrations of other types--namely, that with coarse and
blunted features, or the strumous one, nor any of the intermediates.
These have been discussed chiefly by Dr. Mahomed in the memoir
alluded to above.

In the large experience I have had of sorting photographs, literally
by the thousand, while making experiments with composites, I have
been struck by certain general impressions. The consumptive patients
consisted of many hundred cases, including a considerable proportion
of very ignoble specimens of humanity. Some were scrofulous and
misshapen, or suffered from various loathsome forms of inherited
disease; most were ill nourished. Nevertheless, in studying their
portraits the pathetic interest prevailed, and I returned day after
day to my tedious work of classification, with a liking for my
materials. It was quite otherwise with the criminals. I did not
adequately appreciate the degradation of their expressions for some
time; at last the sense of it took firm hold of me, and I cannot now
handle the portraits without overcoming by an effort the aversion
they suggest.

I am sure that the method of composite portraiture opens a fertile
field of research to ethnologists, but I find it very difficult to
do much single-handed, on account of the difficulty of obtaining the
necessary materials. As a rule, the individuals must be specially
photographed. The portraits made by artists are taken in every
conceivable aspect and variety of light and shade, but for the
purpose in question the aspect and the shade must be the same
throughout. Group portraits would do to work from, were it not for
the strong out-of-door light under which they are necessarily taken,
which gives an unwonted effect to the expression of the faces. Their
scale also is too small to give a sufficiently clear picture when
enlarged. I may say that the scale of the portraits need not be
uniform, as my apparatus enlarges or reduces as required, at the
same time that it superposes the images; but the portraits of the
heads should never be less than twice the size of that of the Queen
on a halfpenny piece.

I heartily wish that amateur photographers would seriously take up
the subject of composite portraiture as applied to different
sub-types of the varying races of men. I have already given more
time to perfecting the process and experimenting with it than I can
well spare.


The differences in the bodily qualities that are the usual subjects
of anthropometry are easily dealt with, and are becoming widely
registered in many countries. We are unfortunately destitute of
trustworthy measurements of Englishmen of past generations to enable
us to compare class with class, and to learn how far the several
sections of the English nation may be improving or deteriorating. We
shall, however, hand useful information concerning our own times to
our successors, thanks principally to the exertions of an
Anthropometric Committee established five years ago by the British
Association, who have collected and partly classified and published
a large amount of facts, besides having induced several institutions,
such as Marlborough College, to undertake a regular system of
anthropometric record. I am not, however, concerned here with the
labours of this committee, nor with the separate valuable
publications of some of its members, otherwise than in one small
particular which appears to show that the English population as a
whole, or perhaps I should say the urban portion of it, is in some
sense deteriorating. It is that the average stature of the older
persons measured by or for the committee has not been found to
decrease steadily with their age, but sometimes the reverse.[1] This
contradicts observations made on the heights of the same men at
different periods, whose stature after middle age is invariably
reduced by the shrinking of the cartilages. The explanation offered
was that the statistical increase of stature with age should be
ascribed to the survival of the more stalwart. On reconsideration, I
am inclined to doubt the adequacy of the explanation, and partly to
account for the fact by a steady, slight deterioration of stature in
successive years; in the urban population owing to the conditions of
their lives, and in the rural population owing to the continual
draining away of the more stalwart of them to the towns.

It cannot be doubted that town life is harmful to the town population.
I have myself investigated its effect on fertility (see Appendix B),
and found that taking on the one hand a number of rural parishes,
and on the other hand the inhabitants of a medium town, the former
reared, nearly twice as many adult grandchildren as the latter. The
vital functions are so closely related that an inferiority in the
production of healthy children very probably implies a loss of
vigour generally, one sign of which is a diminution of stature.

Though the bulk of the population may deteriorate, there are many
signs that the better housed and fed portion of it improves. In the
earlier years of this century the so-called manly sports of boxing
and other feats of strength ranked high among the national amusements.
A man who was [1] successful in these became the hero of a large and
demonstrative circle of admirers, and it is to be presumed that the
best boxer, the best pedestrian, and so forth, was the best adapted
to succeed, through his natural physical gifts. If he was not the
most gifted man in those respects in the whole kingdom, he was
certainly one of the most gifted of them. It therefore does no
injustice to the men of that generation to compare the feats of
their foremost athletes with those of ours who occupy themselves in
the same way. The comparison would probably err in their favour,
because the interest in the particular feats in which our
grandfathers and great-grandfathers delighted are not those that
chiefly interest the present generation, and notwithstanding our
increased population, there are fewer men now who attempt them. In
the beginning of this century there were many famous walking matches,
and incomparably the best walker was Captain Barclay of Ury. His
paramount feat, which was once very familiar to the elderly men of
the present time, was that of walking a thousand miles in a thousand
hours, but of late years that feat has been frequently equalled and
overpassed. I am willing to allow much influence to the modern
conditions of walking under shelter and subject to improved methods
of training (Captain Barclay himself originated the first method,
which has been greatly improved since his time); still the fact
remains that in executing this particular feat, the athletes of the
present day are more successful than those who lived some eighty
years ago. I may be permitted to give an example bearing on the
increased stature of the better housed and fed portion of the nation,
in a recollection of my own as to the difference in height between
myself and my fellow-collegians at Trinity College, Cambridge, in
1840-4. My height is 5 feet 9-3/4 inches, and I recollect perfectly
that among the crowd of undergraduates I stood somewhat taller than
the majority. I generally looked a little downward when I met their
eyes. In later years, whenever I have visited Cambridge, I have
lingered in the ante-chapel and repeated the comparison, and now I
find myself decidedly shorter than the average of the students. I
have precisely the same kind of recollection and the same present
experience of the height of crowds of well-dressed persons. I used
always to get a fair view of what was going on over or between their
heads; I rarely can do so now.

[Footnote 1: _Trans. Brit. Assoc_., 1881, Table V., p. 242; and
remarks by Mr. Roberts, p. 235.]

The athletic achievements at school and college are much superior to
what they used to be. Part is no doubt due to more skilful methods
of execution, but not all. I cannot doubt that the more wholesome
and abundant food, the moderation in drink, the better cooking, the
warmer wearing apparel, the airier sleeping rooms, the greater
cleanliness, the more complete change in holidays, and the healthier
lives led by the women in their girlhood, who become mothers
afterwards, have a great influence for good on the favoured portion
of our race.

The proportion of weakly and misshapen individuals is not to be
estimated by those whom we meet in the streets; the worst cases are
out of sight. We should parade before our mind's eye the inmates of
the lunatic, idiot, and pauper asylums, the prisoners, the patients
in hospitals, the sufferers at home, the crippled, and the
congenitally blind, and that large class of more or less wealthy
persons who flee to the sunnier coasts of England, or expatriate
themselves for the chance of life. There can hardly be a sadder
sight than the crowd of delicate English men and women with narrow
chests and weak chins, scrofulous, and otherwise gravely affected,
who are to be found in some of these places. Even this does not tell
the whole of the story; if there were a conscription in England, we
should find, as in other countries, that a large fraction of the men
who earn their living by sedentary occupations are unfit for
military service. Our human civilised stock is far more weakly
through congenital imperfection than that of any other species of
animals, whether wild or domestic.

It is, however, by no means the most shapely or the biggest
personages who endure hardship the best. Some very shabby-looking
men have extraordinary stamina. Sickly-looking and puny residents in
towns may have a more suitable constitution for the special
conditions of their lives, and may in some sense be better knit and
do more work and live longer than much haler men imported to the
same locality from elsewhere. A wheel and a barrel seem to have the
flimsiest possible constitutions; they consist of numerous separate
pieces all oddly shaped, which, when lying in a heap, look
hopelessly unfitted for union; but put them properly together,
compress them with a tire in the one case and with hoops in the other,
and a remarkably enduring organisation will result. A wheel with a
ton weight on the top of it in the waggons of South Africa will jolt
for thousands of miles over stony, roadless country without
suffering harm; a keg of water may be strapped on the back of a
pack-ox or a mule, and be kicked off and trampled on, and be
otherwise misused for years, without giving way.

I do not propose to enter further into the anthropometric
differences of race, for the subject is a very large one, and this
book does not profess to go into detail. Its intention is to touch
on various topics more or less connected with that of the
cultivation of race, or, as we might call it, with "eugenic" [1]
questions, and to present the results of several of my own separate


Energy is the capacity for labour. It is consistent with all the
robust virtues, and makes a large practice of them possible. It is
the measure of fulness of life; the more energy the more abundance
of it; no energy at all is death; idiots are feeble and listless. In
the inquiries I made on the antecedents of men of science no points
came out more strongly than that the leaders of scientific thought
were generally gifted with remarkable energy, and that they had
[2] inherited the gift of it from their parents and grandparents. I
have since found the same to be the case in other careers.

[Footnote 2: That is, with questions bearing on what is termed in
Greek, _eugenes_, namely, good in stock, hereditarily endowed with
noble qualities. This, and the allied words, _eugeneia_, etc., are
equally applicable to men, brutes, and plants. We greatly want a
brief word to express the science of improving stock, which is by no
means confined to questions of judicious mating, but which,
especially in the case of man, takes cognisance of all influences
that tend in however remote a degree to give to the more suitable
races or strains of blood a better chance of prevailing speedily
over the less suitable than they otherwise would have had. The word
_eugenics_ would sufficiently express the idea; it is at least a
neater word and a more generalised one than _viriculture_, which I
once ventured to use.]

Energy is an attribute of the higher races, being favoured beyond
all other qualities by natural selection. We are goaded into
activity by the conditions and struggles of life. They afford
stimuli that oppress and worry the weakly, who complain and bewail,
and it may be succumb to them, but which the energetic man welcomes
with a good-humoured shrug, and is the better for in the end.

The stimuli may be of any description: the only important matter is
that all the faculties should be kept working to prevent their
perishing by disuse. If the faculties are few, very simple stimuli
will suffice. Even that of fleas will go a long way. A dog is
continually scratching himself, and a bird pluming itself, whenever
they are not occupied with food, hunting, fighting, or love. In
those blank times there is very little for them to attend to besides
their varied cutaneous irritations. It is a matter of observation
that well washed and combed domestic pets grow dull; they miss the
stimulus of fleas. If animals did not prosper through the agency of
their insect plagues, it seems probable that their races would long
since have been so modified that their bodies should have ceased to
afford a pasture-ground for parasites.

It does not seem to follow that because men are capable of doing
hard work they like it. Some, indeed, fidget and fret if they cannot
otherwise work off their superfluous steam; but on the other hand
there are many big lazy fellows who will not get up their steam to
full pressure except under compulsion. Again, the character of the
stimulus that induces hard work differs greatly in different persons;
it may be wealth, ambition, or other object of passion. The solitary
hard workers, under no encouragement or compulsion except their
sense of duty to their generation, are unfortunately still rare
among us.

It may be objected that if the race were too healthy and energetic
there would be insufficient call for the exercise of the pitying and
self-denying virtues, and the character of men would grow harder in
consequence. But it does not seem reasonable to preserve sickly
breeds for the sole purpose of tending them, as the breed of foxes
is preserved solely for sport and its attendant advantages. There is
little fear that misery will ever cease from the land, or that the
compassionate will fail to find objects for their compassion; but at
present the supply vastly exceeds the demand: the land is
overstocked and overburdened with the listless and the incapable.

In any scheme of eugenics, energy is the most important quality to
favour; it is, as we have seen, the basis of living action, and it
is eminently transmissible by descent.


The only information that reaches us concerning outward events
appears to pass through the avenue of our senses; and the more
perceptive the senses are of difference, the larger is the field
upon which our judgment and intelligence can act. Sensation mounts
through a series of grades of "just perceptible differences." It
starts from the zero of consciousness, and it becomes more intense
as the stimulus increases (though at a slower rate) up to the point
when the stimulus is so strong as to begin to damage the nerve
apparatus. It then yields place to pain, which is another form of
sensation, and which continues until the nerve apparatus is destroyed.
Two persons may be equally able just to hear the same faint sound,
and they may equally begin to be pained by the same loud sound, and
yet they may differ as to the number of intermediate grades of
sensation. The grades will be less numerous as the organisation is
of a lower order, and the keenest sensation possible to it will in
consequence be less intense. An artist who is capable of
discriminating more differences of tint than another man is not
necessarily more capable of seeing clearly in twilight, or more or
less intolerant of sunshine. A musician is not necessarily able to
hear very faint sounds, nor to be more startled by loud sounds than
others are. A mechanic who works hard with heavy tools and has rough
and grimy thumbs, insensible to very slight pressures, may yet have
a singularly discriminating power of touch in respect to the
pressures that he can feel.

The discriminative faculty of idiots is curiously low; they hardly
distinguish between heat and cold, and their sense of pain is so
obtuse that some of the more idiotic seem hardly to know what it is.
In their dull lives, such pain as can be excited in them may
literally be accepted with a welcome surprise. During a visit to
Earlswood Asylum I saw two boys whose toe-nails had grown into the
flesh and had been excised by the surgeon. This is a horrible
torture to ordinary persons, but the idiot lads were said to have
shown no distress during the operation; it was not necessary to hold
them, and they looked rather interested at what was being done.
[1] I also saw a boy with the scar of a severe wound on his wrist;
the story being that he had first burned himself slightly by accident,
and, liking the keenness of the new sensation, he took the next
opportunity of repeating the experience, but, idiot-like, he overdid

The trials I have as yet made on the sensitivity of different
persons confirms the reasonable expectation that it would on the
whole be highest among the intellectually ablest. At first, owing to
my confusing the quality of which I am speaking with that of nervous
irritability, I fancied that women of delicate nerves who are
distressed by noise, sunshine, etc., would have acute powers of
discrimination. But this I found not to be the case. In morbidly
sensitive persons both pain and sensation are induced by lower
stimuli than in the healthy, but the number of just perceptible
grades of sensation between them is not necessarily different.

I found as a rule that men have more delicate powers of
discrimination than women, and the business experience of life seems
to confirm this view. The tuners of pianofortes are men, and so I
understand are the tasters of tea and wine, the sorters of wool, and
the like. These latter occupations are well salaried, because it is
of the first moment to the merchant that he should be rightly advised
on the real value of what he is about to purchase or to sell. If the
sensitivity of women were superior to that of men, the self-interest
of merchants would lead to their being [3] always employed; but as
the reverse is the case, the opposite supposition is likely to be
the true one.

[Footnote 3: See "Remarks on Idiocy," by E.W. Graham, M. D.,
_Medical Journal_, January 16, 1875.]

Ladies rarely distinguish the merits of wine at the dinner-table,
and though custom allows them to preside at the breakfast-table, men
think them on the whole to be far from successful makers of tea and

Blind persons are reputed to have acquired in compensation for the
loss of their eyesight an increased acuteness in their other senses;
I was therefore curious to make some trials with my test apparatus,
which I will describe in the next chapter. I was permitted to do so
on a number of boys at a large educational blind asylum, but found
that, although they were anxious to do their best, their performances
were by no means superior to those of other boys. It so happened
that the blind lads who showed the most delicacy of touch and won
the little prizes I offered to excite emulation, barely reached the
mediocrity of the various sighted lads of the same age whom I had
previously tested. I have made not a few observations and inquiries,
and find that the guidance of the blind depends mainly on the
multitude of collateral indications to which they give much heed,
and not in their superior sensitivity to any one of them. Those who
see do not care for so many of these collateral indications, and
habitually overlook and neglect several of them. I am convinced also
that not a little of the popular belief concerning the sensitivity
of the blind is due to exaggerated claims on their part that have
not been verified. Two instances of this have fallen within my own
experience, in both of which the blind persons claimed to have the
power of judging by the echo of their voice and by certain other
feelings, the one when they were approaching objects, even though
the object was so small as a handrail, and the other to tell how far
the door of the room in which he was standing was open. I used all
the persuasion I could to induce each of these persons to allow me
to put their assertions to the test; but it was of no use. The one
made excuses, the other positively refused. They had probably the
same tendency that others would have who happened to be defective in
any faculty that their comrades possessed, to fight bravely against
their disadvantage, and at the same time to be betrayed into some
overvaunting of their capacities in other directions. They would be
a little conscious of this, and would therefore shrink from being

The power of reading by touch is not so very wonderful. A former
Lord Chancellor of England, the late Lord Hatherley, when he was
advanced in years, lost his eyesight for some time owing to a
cataract, which was not ripe to be operated on. He assured me that
he had then learned and practised reading by touch very rapidly.
This fact may perhaps also serve as additional evidence of the
sensitivity of able men.

Notwithstanding many travellers' tales, I have thus far been
unsuccessful in obtaining satisfactory evidence of any general large
superiority of the senses of savages over those of civilised men. My
own experience, so far as it goes, of Hottentots, Damaras, and some
other wild races, went to show that their sense discrimination was
not superior to those of white men, even as regards keenness of
eyesight. An offhand observer is apt to err by assigning to a single
cause what is partly due to others as well. Thus, as regards eyesight,
a savage who is accustomed to watch oxen grazing at a distance
becomes so familiar with their appearance and habits that he can
identify particular animals and draw conclusions as to what they are
doing with an accuracy that may seem to strangers to be wholly
dependent on exceptional acuteness of vision. A sailor has the
reputation of keen sight because he sees a distant coast when a
landsman cannot make it out; the fact being that the landsman
usually expects a different appearance to what he has really to look
for, such as a very minute and sharp outline instead of a large,
faint blur. In a short time a landsman becomes quite as quick as a
sailor, and in some test experiments[1] he was found on the average
to be distinctly the superior. It is not surprising that this should
be so, as sailors in vessels of moderate size have hardly ever the
practice of focussing their eyes sharply upon objects farther off
than the length of the vessel or the top of the mast, say at a
distance of fifty paces. The horizon itself as seen from the deck,
[4] and under the most favourable circumstances, is barely four
miles off, and there is no sharpness of outline in the intervening
waves. Besides this, the life of a sailor is very unhealthy, as
shown by his growing old prematurely, and his eyes must be much
tried by foul weather and salt spray.

[Footnote 4: Gould's _Military and Anthropological Statistics_, p.
530. New York, 1869.]

We inherit our language from barbarous ancestors, and it shows
traces of its origin in the imperfect ways by which grades of
difference admit of being expressed. Suppose a pedestrian is asked
whether the knapsack on his back feels heavy. He cannot find a reply
in two words that cover more varieties than (1) very heavy, (2)
rather heavy, (3) moderate, (4) rather light, (5) very light. I once
took considerable pains in the attempt to draw up verbal scales of
more than five orders of magnitude, using those expressions only
that every cultivated person would understand in the same sense; but
I did not succeed. A series that satisfied one person was not
interpreted in the same sense by another.

The general intention of this chapter has been to show that a
delicate power of sense discrimination is an attribute of a high race,
and that it has not the drawback of being necessarily associated
with nervous irritability.


I will now describe an apparatus I have constructed to test the
delicacy with which weights may be discriminated by handling them. I
do so because the principle on which it is based may be adopted in
apparatus for testing other senses, and its description and the
conditions of its use will illustrate the desiderata and
difficulties of all such investigations.

A series of test weights is a simple enough idea--the difficulty
lies in determining the particular sequence of weights that should
be employed. Mine form a geometric series, for the reason that when
stimuli of all kinds increase by geometric grades the sensations
they give rise to will increase by arithmetic grades, so long as the
stimulus is neither so weak as to be barely felt, nor so strong as
to excite fatigue. My apparatus, which is explained more fully in the
Appendix, consists of a number of common gun cartridge cases filled
with alternate layers of shot, wool, and wadding, and then closed in
the usual way. They are all identical in appearance, and may be said
to differ only in their specific gravities. They are marked in
numerical sequence with the register numbers, 1, 2, 3, etc., but
their weights are proportioned to the numbers of which 1, 2, 3, etc.,
are the logarithms, and consequently run in a geometric series.
Hence the numbers of the weights form a scale of equal degrees of
sensitivity. If a person can just distinguish between the weights
numbered 1 and 3, he can also just distinguish between 2 and 4, 3 and
5, and any other pair of weights of which the register number of
the one exceeds that of the other by 2. Again, his coarseness of
discrimination is exactly double of that of another person who can
just distinguish pairs of weights differing only by 1, such as 1 and
2, 2 and 3, 3 and 4, and so on. The testing is performed by handing
pairs of weights to the operatee until his power of discrimination
is approximately made out, and then to proceed more carefully. It is
best now, for reasons stated in the Appendix, to hand to the
operatee sequences of three weights at a time, after shuffling them.
These he has to arrange in their proper order, with his eyes shut,
and by the sense of their weight alone. The operator finally records
the scale interval that the operatee can just appreciate, as being
the true measure of the coarseness (or the inverse measure of the
delicacy) of the sensitivity of the operatee.

It is somewhat tedious to test many persons in succession, but any
one can test his own powers at odd and end times with ease and nicety,
if he happens to have ready access to suitable apparatus.

The use of tests, which, objectively speaking, run in a geometric
series, and subjectively in an arithmetic one, may be applied to
touch, by the use of wire-work of various degrees of fineness; to
taste, by stock bottles of solutions of salt, etc., of various
strengths; to smell, by bottles of attar of rose, etc., in various
degrees of dilution.

The tests show the sensitivity at the time they are made, and give
an approximate measure of the discrimination with which the operatee
habitually employs his senses. It does not measure his capacity for
discrimination, because the discriminative faculty admits of much
education, and the test results always show increased delicacy after
a little practice. However, the requirements of everyday life
educate all our faculties in some degree, and I have not found the
performances with test weights to improve much after a little
familiarity with their use. The weights have, as it were, to be
played with at first, then they must be tried carefully on three or
four separate occasions.

I did not at first find it at all an easy matter to make test
weights so alike as to differ in no other appreciable respect than
in their specific gravity, and if they differ and become known apart,
the knowledge so acquired will vitiate future judgments in various
indirect ways. Similarity in outward shape and touch was ensured by
the use of mechanically-made cartridge cases; dissimilarity through
any external stain was rendered of no hindrance to the experiment by
making the operatee handle them in a bag or with his eyes shut. Two
bodies may, however, be alike in weight and outward appearance and
yet behave differently when otherwise mechanically tested, and,
consequently, when they are handled. For example, take two eggs, one
raw and the other hard boiled, and spin them on the table; press the
finger for a moment upon either of them whilst it is still spinning:
if it be the hard-boiled egg it will stop as dead as a stone: if it
be the raw egg, after a little apparent hesitation, it will begin
again to rotate. The motion of its shell had alone been stopped; the
internal part was still rotating and this compelled the shell to
follow it. Owing to this cause, when we handle the two eggs, the one
feels "quick" and the other does not. Similarly with the cartridges,
when one is rather more loosely packed than the others the
difference is perceived on handling them. Or it may have one end
heavier than the other, or else its weight may not be equally
distributed round its axis, causing it to rest on the table with the
same part always lowermost; differences due to these causes are also
easily perceived when handling the cartridges. Again, one of two
similar cartridges may balance perfectly in all directions, but the
weight of one of them may be disposed too much towards the ends, as
in a dumb-bell, or gathered too much towards the centre. The period
of oscillation will differ widely in the two cases, as may be shown
by suspending the cartridges by strings round their middle so that
they shall hang horizontally, and then by a slight tap making them
spin to and fro round the string as an axis.

The touch is very keen in distinguishing all these peculiarities. I
have mentioned them, and might have added more, to show that
experiments on sensitivity have to be made in the midst of pitfalls
warily to be avoided. Our apparently simplest perceptions are very
complex. We hardly ever act on the information given by only one
element of one sense, and our sensitivity in any desired direction
cannot be rightly determined except by carefully-devised apparatus
judiciously used.


I contrived a small whistle for conveniently ascertaining the upper
limits of audible sound in different persons, which Dr. Wollaston
had shown to vary considerably. He used small pipes, and found much
difficulty in making them. I made a very small whistle from a brass
tube whose internal diameter was less than one-tenth of an inch in
diameter. A plug was fitted into the lower end of the tube, which
could be pulled out or pushed in as much as desired, thereby causing
the length of the bore of the whistle to be varied at will. When the
bore is long the note is low; when short, it is high. The plug was
graduated, so that the precise note produced by the whistle could be
determined by reading off the graduations and referring to a table.
(See Appendix.)

On testing different persons, I found there was a remarkable falling
off in the power of hearing high notes as age advanced. The persons
themselves were quite unconscious of their deficiency so long as
their sense of hearing low notes remained unimpaired. It is an only
too amusing experiment to test a party of persons of various ages,
including some rather elderly and self-satisfied personages. They
are indignant at being thought deficient in the power of hearing, yet
the experiment quickly shows that they are absolutely deaf to shrill
notes which the younger persons hear acutely, and they commonly
betray much dislike to the discovery. Every one has his limit, and
the limit at which sounds become too shrill to be audible to any
particular person can be rapidly determined by this little instrument.
Lord Rayleigh and others have found that sensitive flames are
powerfully affected by the vibrations of whistles that are too rapid
to be audible to ordinary ears.

I have tried experiments with all kinds of animals on their
powers of hearing shrill notes. I have gone through the whole
of the Zoological Gardens, using an apparatus arranged for the
purpose. It consists of one of my little whistles at the end of a
walking-stick--that is, in reality, a long tube; it has a bit of
india-rubber pipe under the handle, a sudden squeeze upon which
forces a little air into the whistle and causes it to sound. I hold
it as near as is safe to the ears of the animals, and when they are
quite accustomed to its presence and heedless of it, I make it sound;
then if they prick their ears it shows that they hear the whistle; if
they do not, it is probably inaudible to them. Still, it is very
possible that in some cases they hear but do not heed the sound. Of
all creatures, I have found none superior to cats in the power of
hearing shrill sounds; it is perfectly remarkable what a faculty
they have in this way. Cats, of course, have to deal in the dark
with mice, and to find them out by their squealing. Many people
cannot hear the shrill squeal of a mouse. Some time ago, singing
mice were exhibited in London, and of the people who went to hear
them, some could hear nothing, whilst others could hear a little, and
others again could hear much. Cats are differentiated by natural
selection until they have a power of hearing all the high notes made
by mice and other little creatures that they have to catch. A cat
that is at a very considerable distance, can be made to turn its ear
round by sounding a note that is too shrill to be audible by almost
any human ear. Small dogs also hear very shrill notes, but large
ones do not. I have walked through the streets of a town with an
instrument like that which I used in the Zoological Gardens, and
made nearly all the little dogs turn round, but not the large ones.
At Berne, where there appear to be more large dogs lying idly about
the streets than in any other town in Europe, I have tried the
whistle for hours together, on a great many large dogs, but could
not find one that heard it. Ponies are sometimes able to hear very
high notes. I once frightened a pony with one of these whistles in
the middle of a large field. My attempts on insect hearing have been


When shall we have anthropometric laboratories, where a man may,
when he pleases, get himself and his children weighed, measured, and
rightly photographed, and have their bodily faculties tested by the
best methods known to modern science? The records of growth of
numerous persons from childhood to age are required before it can be
possible to rightly appraise the effect of external conditions upon
development, and records of this kind are at present non-existent.
The various measurements should be accompanied by photographic
studies of the features in full face and in profile, and on the same
scale, for convenience of comparison.

We are all lazy in recording facts bearing on ourselves, but parents
are glad enough to do so in respect to their children, and they
would probably be inclined to avail themselves of a laboratory where
all that is required could be done easily and at small cost. These
domestic records would hereafter become of considerable biographical
interest. Every one of us in his mature age would be glad of a series
of pictures of himself from childhood onwards, accompanied by
physical records, and arranged consecutively with notes of current
events by their sides. Much more would he be glad of similar
collections referring to his father, mother, grandparents, and other
near relatives. It would be peculiarly grateful to the young to
possess likenesses of their parents and those whom they look upon as
heroes, taken when they were of the same age as themselves. Boys are
too apt to think of their parents as having always been elderly men,
because they have insufficient data to construct imaginary pictures
of them as they were in their youth.

The cost of taking photographs in batches is so small, and the time
occupied is so brief, when the necessary preparations have been made
and the sitters are ready at hand, that a practice of methodically
photographing schoolboys and members of other large institutions
might easily be established. I, for one, should dearly prize the
opportunity of visiting the places where I have been educated, and
of turning over pages showing myself and my companions as we were in
those days. But no such records exist; the institutions last and
flourish, the individuals who pass through them are dispersed and
leave few or no memorials behind. It seems a cruel waste of
opportunity not to make and keep these brief personal records in a
methodical manner. The fading of ordinary photographic prints is no
real objection to keeping a register, because they can now be
reproduced at small charge in permanent printers' ink, by the
autotype and other processes.

I have seen with admiration, and have had an opportunity of availing
myself of, the newly-established library of well-ordered folios at
the Admiralty, each containing a thousand pages, and each page
containing a brief summary of references to the life of a particular
seaman. There are already 80,000 pages, and owing to the excellent
organisation of the office it is a matter of perfect ease to follow
out any one of these references, and to learn every detail of the
service of any seaman. A brief register of measurements and events in
the histories of a large number of persons, previous to their
entering any institution and during their residence in it, need not
therefore be a difficult matter to those who may take it in hand
seriously and methodically.

The recommendation I would venture to make to my readers is to
obtain photographs and ordinary measurements periodically of
themselves and their children, making it a family custom to do so,
because, unless driven by some custom, the act will be postponed
until the opportunity is lost. Let those periodical photographs be
full and side views of the face on an adequate scale, adding any
others that may be wished, but not omitting these. As the portraits
accumulate have collections of them autotyped. Keep the prints
methodically in a family register, writing by their side careful
chronicles of illness and all such events as used to find a place on
the fly-leaf of the Bible of former generations, and inserting other
interesting personal facts and whatever anthropometric data can be

Those who care to initiate and carry on a family chronicle
illustrated by abundant photographic portraiture, will produce a
work that they and their children and their descendants in more
remote generations will assuredly be grateful for. The family tie
has a real as well as a traditional significance. The world is
beginning to awaken to the fact that the life of the individual is
in some real sense a prolongation of those of his ancestry. His
vigour, his character, and his diseases are principally derived from
theirs; sometimes his faculties are blends of ancestral qualities;
but more frequently they are mosaics, patches of resemblance to one
or other of them showing now here and now there. The life-histories
of our relatives are prophetic of our own futures; they are far more
instructive to us than those of strangers, far more fitted to
encourage and to forewarn us. If there be such a thing as a natural
birthright, I can conceive of none superior to the right of the
child to be informed, at first by proxy through his guardians, and
afterwards personally, of the life-history, medical and other, of
his ancestry. The child is thrust into existence without his having
any voice at all in the matter, and the smallest amend that those
who brought him here can make, is to furnish him with all the
guidance they can, including the complete life-histories of his near

The investigation of human eugenics--that is, of the conditions
under which men of a high type are produced--is at present extremely
hampered by the want of full family histories, both medical and
general, extending over three or four generations. There is no such
difficulty in investigating animal eugenics, because the generations
of horses, cattle, dogs, etc., are brief, and the breeder of any
such stock lives long enough to acquire a large amount of experience
from his own personal observation. A man, however, can rarely be
familiar with more than two or three generations of his
contemporaries before age has begun to check his powers; his working
experience must therefore be chiefly based upon records. Believing,
as I do, that human eugenics will become recognised before long as a
study of the highest practical importance, it seems to me that no
time ought to be lost in encouraging and directing a habit of
compiling personal and family histories. If the necessary materials
be brought into existence, it will require no more than zeal and
persuasiveness on the part of the future investigator to collect as
large a store of them as he may require.


The importance of submitting our faculties to measurement lies in
the curious unconsciousness in which we are apt to live of our
personal peculiarities, and which our intimate friends often fail to
remark. I have spoken of the ignorance of elderly persons of their
deafness to high notes, but even the existence of such a peculiarity
as colour blindness was not suspected until the memoir of Dalton in
1794. That one person out of twenty-nine or thereabouts should be
unable to distinguish a red from a green, without knowing that he
had any deficiency of colour sense, and without betraying his
deficiency to his friends, seems perfectly incredible to the other
twenty-eight; yet as a matter of fact he rarely does either the one
or the other. It is hard to convince the colour-blind of their own
infirmity. I have seen curious instances of this: one was that of a
person by no means unpractised in physical research, who had been
himself tested in matching colours. He gave me his own version of
the result, to the effect that though he might perhaps have fallen a
little short of perfection as judged by over-refined tests, his
colour sense was for all practical purposes quite good. On the other
hand, the operator assured me that when he had toned the intensities
of a pure red and a pure green in a certain proportion, the person
ceased to be able to distinguish between them! Colour blindness is
often very difficult to detect, because the test hues and tints may
be discriminated by other means than by the normal colour sense.
Ordinary pigments are never pure, and the test colours may be
distinguished by those of their adventitious hues to which the
partly colour-blind man may be sensitive. We do not suspect
ourselves to be yellow-blind by candle light, because we enjoy
pictures in the evening nearly or perhaps quite as much as in the day
time; yet we may observe that a yellow primrose laid on the white
table-cloth wholly loses its colour by candle light, and becomes as
white as a snowdrop.

In the inquiries I made on the hereditary transmission of capacity,
I was often amused by the naive remark of men who had easily
distanced their competitors, that they ascribed their success to
their own exertions. They little recognised how much they owed to
their natural gifts of exceptional capacity and energy on the one
hand, and of exceptional love for their special work on the other.

In future chapters I shall give accounts of persons who have unusual
mental characteristics as regards imagery, visualised numerals,
colours connected with sounds and special associations of ideas,
being unconscious of their peculiarities; but I cannot anticipate
these subjects here, as they all require explanation. It will be
seen in the end how greatly metaphysicians and psychologists may err,
who assume their own mental operations, instincts, and axioms to be
identical with those of the rest of mankind, instead of being
special to themselves. The differences between men are profound, and
we can only be saved from living in blind unconsciousness of our own
mental peculiarities by the habit of informing ourselves as well as
we can of those of others. Examples of the success with which this
can be done will be found farther on in the book.

I may take this opportunity of remarking on the well-known
hereditary character of colour blindness in connection with the fact,
that it is nearly twice as prevalent among the Quakers as among the
rest of the community, the proportions being as 5.9 to 3.5 per cent.
[1] We might have expected an even larger ratio. Nearly every Quaker
is descended on both sides solely from members of a group of men and
women who segregated themselves from the rest of the world five or
six generations ago; one of their strongest opinions being that the
fine arts were worldly snares, and their most conspicuous practice
being to dress in drabs. A born artist could never have consented to
separate himself from his fellows on such grounds; he would have
felt the profession of those opinions [5] and their accompanying
practices to be a treason to his aesthetic nature. Consequently few
of the original stock of Quakers are likely to have had the
temperament that is associated with a love for colour, and it is in
consequence most reasonable to believe that a larger proportion of
colour-blind men would have been found among them than among the
rest of the population.

[Footnote 5: _Trans. Ophthalmological Soc_., 1881, p. 198.]

Again, Quakerism is a decreasing sect, weakened by yearly desertions
and losses, especially as the act of marriage with a person who is
not a member of the Society is necessarily followed by exclusion
from it. It is most probable that a large proportion of the
deserters would be those who, through reversion to some bygone
ancestor, had sufficient artistic taste to make a continuance of
Quaker practices too irksome to be endured. Hence the existing
members of the Society of Friends are a race who probably contained
in the first instance an unduly large proportion of colour-blind men,
and from whose descendants many of those who were not born colour
blind have year by year been drafted away. Both causes must have
combined with the already well-known tendency of colour blindness to
hereditary transmission, to cause it to become a characteristic of
their race. Dalton, who first discovered its existence, as a
personal peculiarity of his own, was a Quaker to his death; Young,
the discoverer of the undulatory theory of light, and who wrote
specially on colours, was a Quaker by birth, but he married outside
the body and so ceased to belong to it.


The object of statistical science is to discover methods of
condensing information concerning large groups of allied facts into
brief and compendious expressions suitable for discussion. The
possibility of doing this is based on the constancy and continuity
with which objects of the same species are found to vary. That is to
say, we always find, after sorting any large number of such objects
in the order (let us suppose) of their lengths, beginning with the
shortest and ending with the tallest, and setting them side by side
like a long row of park palings between the same limits, their upper
outline will be identical. Moreover, it will run smoothly and not in
irregular steps. The theoretical interpretation of the smoothness of
outline is that the individual differences in the objects are caused
by different combinations of a large number of minute influences; and
as the difference between any two adjacent objects in a long row
must depend on the absence in one of them of some single influence,
or of only a few such, that were present in the other, the amount of
difference will be insensible. Whenever we find on trial that the
outline of the row is not a flowing curve, the presumption is that
the objects are not all of the same species, but that part are
affected by some large influence from which the others are free;
consequently there is a confusion of curves. This presumption is
never found to be belied.

It is unfortunate for the peace of mind of the statistician that the
influences by which the magnitudes, etc., of the objects are
determined can seldom if ever be roundly classed into large and small,
without intermediates. He is tantalised by the hope of getting hold
of sub-groups of sufficient size that shall contain no individuals
except those belonging strictly to the same species, and he is almost
constantly baffled. In the end he is obliged to exercise his
judgment as to the limit at which he should cease to subdivide. If
he subdivides very frequently, the groups become too small to have
statistical value; if less frequently, the groups will be less truly

A species may be defined as a group of objects whose individual
differences are wholly due to different combinations of the same set
of minute causes, no one of which is so powerful as to be able by
itself to make any sensible difference in the result. A well-known
mathematical consequence flows from this, which is also universally
observed as a fact, namely, that in all species the number of
individuals who differ from the average value, up to any given amount,
is much greater than the number who differ more than that amount,
and up to the double of it. In short, if an assorted series be
represented by upright lines arranged side by side along a
horizontal base at equal distances apart, and of lengths
proportionate to the magnitude of the quality in the corresponding
objects, then their shape will always resemble that shown in Fig. 1.

The form of the bounding curve resembles that which is called in
architectural language an ogive, from "augive," an old French word
for a cup, the figure being not unlike the upper half of a cup lying
sideways with its axis horizontal. In consequence of the multitude
of mediocre values, we always find that on either side of the
middlemost ordinate _Cc_, which is the median value and may be
accepted as the average, there is a much less rapid change of height
than elsewhere. If the figure were pulled out sideways to make it
accord with such physical conceptions as that of a row of men
standing side by side, the middle part of the curve would be
apparently horizontal.

[Illustration: Fig. 1.]

[Illustration: Fig. 2.]

The mathematical conception of the curve is best expressed in Fig. 2,
where PQ represents any given deviation from the average value, and
the ratio of PO to AB represents the relative probability of its
occurrence. The equation to the curve and a discussion of its
properties will be found in the _Proceedings of the Royal Society_,
No. 198, 1879, by Dr. M'Alister. The title of the paper is the
"Law of the Geometric Mean," and it follows one by myself on
"The Geometric Mean in Vital and Social Statistics."

We can lay down the ogive of any quality, physical or mental,
whenever we are capable of judging which of any two members of the
group we are engaged upon has the larger amount of that quality. I
have called this the method of statistics by intercomparison. There
is no bodily or mental attribute in any race of individuals that can
be so dealt with, whether our judgment in comparing them be guided
by common-sense observation or by actual measurement, which cannot
be gripped and consolidated into an ogive with a smooth outline, and
thenceforward be treated in discussion as a single object.

It is easy to describe any given ogive which has been based upon
measurements, so that it may be drawn from the description with
approximate truth. Divide AB into a convenient number of fractional
parts, and record the height of the ordinates at those parts. In
reproducing the ogive from these data, draw a base line of any
convenient length, divide it in the same number of fractional parts,
erect ordinates of the stated lengths at those parts, connect their
tops with a flowing line, and the thing is done. The most convenient
fractional parts are the middle (giving the median), the outside
quarters (giving the upper and lower quartiles), and similarly the
upper and lower octiles or deciles. This is sufficient for most
purposes. It leaves only the outer eighths or tenths of the cases
undescribed and undetermined, except so far as may be guessed by,
the run of the intermediate portion of the curve, and it defines all
of the intermediate portion with as close an, approximation as is
needed for ordinary or statistical purposes.

Thus the heights of all but the outer tenths of the whole body of
adult males of the English professional classes may be derived from
the five following ordinates, measured in inches, of which the outer
pair are deciles:--

67.2; 67.5; 68.8; 70.3; 71.4.

Many other instances will be found in the Report of the
Anthropometric Committee of the British Association in 1881,
pp. 245-257.

When we desire to compare any two large statistical groups, we may
compare median with median, quartiles with quartiles, and octiles
with octiles; or we may proceed on the method to be described in the
next paragraph but one.

We are often called upon to define the position of an individual in
his own series, in which case it is most conformable to usage to
give his centesimal grade--that is, his place on the base line
AB--supposing it to be graduated from 0 deg. to 100 deg. In reckoning
this, a confusion ought to be avoided between "graduation" and "rank,"
though it leads to no sensible error in practice. The first of the
"park palings" does not stand at A, which is 0 deg., nor does the
hundredth stand at B, which is 100 deg., for that would make 101 of them:
but they stand at 0 deg.5 and 99 deg.5 respectively. Similarly, all
intermediate _ranks_ stand half a degree short of the _graduation_
bearing the same number. When the class is large, the value of half
a place becomes extremely small, and the rank and graduation may be
treated as identical.

Examples of method of calculating a centesimal position:--

1. A child A is classed after examination as No. 5 in a class of 27
children; what is his centesimal graduation?

_Answer_.--If AB be divided into 27 graduations, his rank of No. 5

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