Finger Prints

by Francis Galton

As regards other forms of natural selection, we know that races are kept pure by the much more frequent destruction of those individuals who depart the more widely from the typical centre. But natural selection was shown to be inoperative in respect to individual varieties of patterns, and unable to exercise the slightest check upon their vagaries. Yet, for all that, the loops and other classes of patterns are isolated from one another just as thoroughly and just in the same way as are the genera or species of plants and animals. There is no statistical difference between the form of the law of distribution of individual Loops about their respective typical centres, and that of the law by which, say, the Shrimps described in Mr. Weldon’s recent memoirs (Proc. Roy. Soc., 1891 and 1892) are distributed about theirs. In both cases the distribution is in quasi-accordance with the theoretical law of Frequency of Error, this form of distribution being entirely caused in the patterns, by internal conditions, and in no way by natural selection in the ordinary sense of that term.

It is impossible not to recognise the fact so clearly illustrated by these patterns in the thumbs, that natural selection has no monopoly of influence in the construction of genera, but that it could be wholly dispensed with, the internal conditions acting by themselves being sufficient. When the internal conditions are in harmony with the external ones, as they appear to be in all long-established races, their joint effects will curb individual variability more tightly than either could do by itself. The normal character of the distribution about the typical centre will not be thereby interfered with. The probable divergence (= probable error) of an individual taken at random, will be lessened, and that is all.

Not only is it impossible to substantiate a claim for natural selection, that it is the sole agent in forming genera, but it seems, from the experience of artificial selection, that it is scarcely competent to do so by favouring mere varieties, in the sense in which I understand the term.

My contention is that it acts by favouring small sports. Mere varieties from a common typical centre blend freely in the offspring, and the offspring of every race whose statistical characters are constant, necessarily tend, as I have often shown, to regress towards their common typical centre. Sports, on the other hand, do not blend freely; they are fresh typical centres or sub-species, which suddenly arise we do not yet know precisely through what uncommon concurrence of circumstance, and which observations show to be strongly transmissible by inheritance.

A mere variety can never establish a sticking-point in the forward course of evolution, but each new sport affords one. A substantial change of type is effected, as I conceive, by a succession of small changes of typical centre, each more or less stable, and each being in its turn favoured and established by natural selection, to the exclusion of its competitors. The distinction between a mere variety and a sport is real and fundamental. I argued this point in Natural Inheritance, but had then to draw my illustrations from non-physiological experiences, no appropriate physiological ones being then at hand: this want is now excellently supplied by observations of the patterns on the digits.

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INDEX

AH, number of ridges in, [200]
Allix, [60]
A. L. W. system, [80]
Ambiguities in minutiæ, [91], [111]
America, [163]
Anthropometric laboratory, [4], [35]
Arches, [7], [75], [78];
interpretations of, [114], [193]
Artisans, [59]
Artists, [58]
Assyrian bricks, [25]
Atkinson, R. F., [192]
Author, the, finger prints of, [8], [58], [73]
Axis of pattern, [68]
Ball for inking, [42]
Ball of thumb, [96]
Basques, [18], [192]
Bearings as by compass, [84]
Beech, Dr. Fletcher, [197]
Benzole, [36], [41]
Bertillon, [2], [15], [154], [169];
Bertillonage, [155], [164], [167]
Bewick, [26]
Bible, the, [22]
Bifurcations, [91]
Binomial law, [11], [112]
Bird’s nest, [34]
Blacklead, [49]
Blood as ink, [45]
Bowditch, H. P., Professor, [47]
British Museum, [25]
Brobdingnags, [1]
Brothers, [171]
Burns of finger, [59]
C. set of standard patterns, [177]
Callosities, [59]
Cambo, [18], [192]
Camera lucida, [52], [104]
Cards, [38];
keeping in order, [145]
Casts, [49]
Centesimal scale, [12], [17], [124], [129], [182]
Cheiromancy, [1], [26];
creases, [56]
Chequer-work, [106]
Chess board, [106]
Chinese deed, [24];
money, [25];
cheiromancy, [26];
registration of Chinese, [26], [152]
Cicatrix, [59]
Circular patterns, optical illusion, [77]
Collins, F. H., [17], [21], [177], [190], [193]
Collodion, [51]
Colour-blindness, [71]
Comparison of prints, [90], [167]
Compass bearings, [84]
Compasses, test by the points of, [61]
Copper sheeting for inking, [42];
for smoking, [48]
Cores, [6], [76], [145]
Correlation, [158]
Couplets of digits, [119];
of A and B brothers, [172]
Creases, [1], [56];
in infant, [57]
Criminals, [149]
Crosse, Dr., [192]
Cylinder, revolving, [49]
Dabs by the finger, [40], [90], [153]
Darenth Asylum, [19], [197]
Demography, Congress of, [163]
Deserters, [149], [164]
Development, [58]
Digits, peculiarities of, [114]
Direction of twist, [78]
Divergence of ridges, [68]
Drawing master, [48]
Ducts, [57]
Dyes, [44]
Ear-marking the A, B sets of brothers, [172]
Embryology, [58]
Enclosures within ridges, [92]
English, the, [17], [192]
Enlargements, [51]

Envelopes to rods or staples, [76]
Error, law of, [19], [198];
“probable,” [199]
Evidential Value, Chap. VII., [100]
Evolution, [20], [60]
Eyes in patterns, [143]
Fauld, Mr., [26]
Feet, prints of, [45];
ridges on, [57], [58]
Féré, M., [197]
Ferris, Major, [149]
Ferro-prussiate process, [51], [53], [90]
File, [63]
Flexure, lines of, in palm, [56]
Focus of eye, range of, [72]
Folders;—inked, [42];
smoked, [48]
Foot-paths, [107]
Forgeot, Dr., [46]
Forks, [91]
Fraternity, [16], [171]
Frequency of error, law of, [19], [198]
Funnel, [36]
Furrows, not followed, [82]
G——, Sir W., [89], [97]
Genera, Chap. XIII., [198];
the nine chief genera, [6], [80]
Glass, temporary prints on, [30];
etched, [47];
for lantern, [51]
Glue, [48]
Goldie, Sir G. T., [192]
Granulations on rollers, [34]
Greenleaf, Col. C. R., [164]
Gulliver, [1]
Gum, [48]
Gutta-percha, [50]
Hand, [23], [45]
Harrild, Messrs., [36], [41]
Hawksley, [42]
Haycraft, Dr. J. B., [51]
Head-length and breadth, [158]
Hebrews, [18], [192], [194]
Herbette, M., [168]
Heredity, Chap. XI., [170];
see also [16]
Herschel, Sir W. J., [4], [9], [27];
instructions for printing, [45];
data for persistence, [89];
right fore-finger of, [95];
official experience, [27], [149], [153]
Hindoos, [152]
I (or Inner side), [70]
Identification, [147];
see Jezebel, [113]
Idiots, [8], [19], [59], [197]
Illusion, [66], [77]
Indexing, power of, [14], [139], [167];
methods of, [131];
specimen of, [133];
search in, [166]
India-rubber for roller, [40]
Ink, printer’s, [37];
for stamp, [45]
Inner side, [70]
Interpolation of ridges, [102], [104]
Interspace, [54], [67]
Interval, equally discernible, [65], [101]
Islands, [92]
Japan, [23], [26]
Jews, [18], [192], [194]
Jezebel, [113]
Kensington, S., my laboratory at, [4], [35]
Klaatsch, Dr. H., [60]
Kollmann, Dr. A., [58]
Labels, gummed, as for luggage, [48]
Laboratory, anthropometric, [4], [35]
Labourers, [59], [197]
Lace, [9], [98]
Ladies’ hands, ridges on, [32]
Language, inadequacy of, [172]
Lankester, Prof. Ray, [45]
Left and right, [70]
Lenses, [72]
Letters, alike when reversed, [71]
Licked paper, [48]
Linen-tester (lens), [73]
Linseed oil, [37]
Litharge, [35]
Lithography, [43]
Loops, [7], [75], [78];
predominance of, [101];
relationships of, [184];
on thumbs, [200];
typical shape of, [207]
Lying Bob, [27]
Lyon, [155]
Mammalia, [60]
Marseille, [155]
Measurement of patterns, [82]
Memoirs by the author, [3]
Methods of Indexing, Chap. IX., [131]
Methods of Printing, Chap. III., [30]
Mica, [47], [51]
Minutiæ, [54];
ambiguities in, [91], [99]
Monkey pattern, [18], [54], [77];
ridges on tail, [60];
Purkenje on, [86], [88];
stuffed, [97]
Morgue, [148];
see Jezebel, [113]
Mould for casting rollers, [40]
Mountain ranges, [32]
Mucilage, [48]
Mummies, ridges still visible, [97]
Nail-marks, [25], [67]
Natural selection, [20], [210]
Negro, [18], [192], [195];
cheiromancy, [26]
Ngeu-yang-siun, [25]
Notes, musical, [63]

Oil, oxidisation of, [34], [43];
for ink, [37]
Orientation, [68]
Outer side, [70]
Outlines, [6], [69];
followed with a point, [74]
Overtones, [63]
Pacinian bodies, [60]
Pad for stamp, [32], [44];
of paper, [38]
Palm of the hand, [54], [88], [113]
Palmistry, [1], [26];
see Cheiromancy, [56]
Panmixia, [20], [209]
Pantagraph, [52]
Paper in pads, [38];
see [Cards]
Papillæ, [60]
Paraffin, [36]
Paris, [155]
Passports, [15], [149]
Paste, [48]
Patterns: Their Outlines and Cores, Chap. V., [64];
see also [2], [54], [170];
number of easily distinguishable patterns, [100];
standard, [74], [80];
ditto C. set, [177];
percentage frequency of, [115]
Peculiarities of the Digits, Chap. VIII., [114]
Persistence, Chap. VI., [89]
Personal Identification, Chap. X., [147];
see also [16], [113];
lecture on, [2]
Photographers, [147];
photographs, [3], [51]
Plots, triangular, [67], [82]
Plumbago, [49]
Pocket printing apparatus, [40]
Points of reference, [90]
Poole, Mr. S. L., [25]
Pores, [57]
Previous Use of Finger Prints, Chap. II., [22]
Printing, the methods of, [30];
printer’s ink, [35]
Prism, [52], [104]
Purkenje’s Commentatio, [84];
see also [8], [64], [67];
on slope of loop, [119]
Races and Classes, Chap. XII., [192];
see also [17]
Radial, [70]
Random events, [172];
see also [126]
Razor, prints on, [30]
Reconstruction of hidden ridges, [102]
Reeves and Co., [35]
Registration in India, [28], [151]
Regression, [21], [171]
Relationship in fingers, [12], [123];
fraternal, [171], [175];
in twins, [185];
filial, [190];
ditto of like-patterned parents, [187];
in patterns, [178];
paternal and maternal, [190]
Reticulation, [108]
Reversals, [43], [71]
Ridges and Their Uses, Chap. IV., [54];
see also low relief of ridges, [32];
counting them, [73];
ridge-interval, [62]:—measurement by, [83];
squares of one in the side, [102];
of six, [103];
of five, [107], [111]
Right and left, [70]
Robinson, Dr. Louis, [45]
Rods, [76]
Rolled prints, [7], [39], [68]
Roller, [36];
small, [40]
Royal Institution, [2]
Sand, ridges on, [54]
Scars, [59], [97]
Seal, [22];
sealing-wax casts, [50]
Seamstresses, [59]
Selection, [20], [209]
Shrimps, [210]
Signalements, [156]
Size (glue), [48], [49]
Skin disease on fingers, [122]
Slab, [4], [35], [41]
Slopes, [136];
on fore-finger, [118]
Smart, Major Charles, [164]
Smoke-prints, [47]
Snow on mountain ranges, [32]
Soda (washing), [36], [41]
Spielman, Isidore, Mr., [192]
Spirals, [74]
Sports, [20], [211]
Squares (interpolations), [10], [101]
Standard patterns, [74], [76];
the C. set, [177]
Staples, [76], [83]
Stereoscope, [9]
Students, in Art and Science, [197]
Surnames, Hindoo and Chinese, [14], [152]
Swift, Dean, [1]
Symbols for patterns, [144]
Systems of ridges on palm, [54]
Tables, see list of, p. [xiii.]
Tabor, Mr., [26]
Tabulations, [179]
Tang dynasty, [25]
Tattoo marks, [97]
Taylor, T. Meadows, Mr., [24]
Teeth, [166]
Tests of calculated Randoms, [173];
of classification, [179]
Thompson, Gilbert, Mr., [27], [44]
Thrills, their relation to notes, [63]
Thumb, loops on, [200];
ball of, [96], [98]
Tipsahi, [24]

Titchener, E. B., Mr., [62]
Title-page, prints on, [8], [58], [73];
index-number to them, [135]
Toes, [57]
Tools, callosities caused by, [59]
Transitional patterns, [79], [143], [178]
Triangular plots, [67], [86], [87]
Turpentine, [36]
Twins, [17], [167], [185]
Twist, direction of, [78]
Type, [19], [198]
Ulnar, [70]
United States, system used in, [15], [164]
Variation, [20], [211]
Varnish, prints on when undried, [50]
Velvet, [63]
Wall-paper, [66]
Water colours, [44]
Wax;—sealing, [50];
dentist’s, [50]
Weldon, Prof., [210]
Welsh, the, [17], [192]
Wen-teh, the Empress, [25]
Whitening, [49]
Whorls, [7], [75], [78]
Wundt, Professor, laboratory at Leipzig, [62]

THE END