The “C” set of standard patterns, for prints of the Right Hand.


1
2
3
4
5
6
7
8
9

10
11
12
13
14
15
16
17
18
19

20
21
22
23
24
25
26
27
28
29

30
31
32
33
34
35
36
37
38
39

40
41
42
43
44
45
46
47
48
49

50
51
52
53

With the view of obtaining a more satisfactory result the patterns were subdivided under fifty-three heads, and an experiment was made with the fore, middle, and ring-fingers of 150 fraternal couplets (300 individuals and 900 digits) by Mr. F. Howard Collins, who kindly undertook the considerable labour of indexing and tabulating them.

The provisional list of standard patterns published in the Phil. Trans. was not appropriate for this purpose. It related chiefly to thumbs, and consequently omitted the tented arch; it also referred to the left hand, but in the following tabulations the right hand has been used; and its numbering is rather inconvenient. The present set of fifty-three patterns has faults, and cannot be considered in any way as final, but it was suitable for our purposes and may be convenient to others; as Mr. Collins worked wholly by it, it may be distinguished as the “C. set.” The banded patterns, 24-31, are very rarely found on the fingers, but being common on the thumb, were retained, on the chance of our requiring the introduction of thumb patterns into the tabulations. The numerals refer to the patterns as seen in impressions of the right hand only. [They would be equally true for the patterns as seen on the fingers themselves of the left hand.] For impressions of the left hand the numerals up to 7 inclusive would be the same, but those of all the rest would be changed. These are arranged in couplets, the one member of the couplet being a reversed picture of the other, those in each couplet being distinguished by severally bearing an odd and an even number. Therefore, in impressions of the left hand, 8 would have to be changed into 9, and 9 into 8; 10 into 11, and 11 into 10; and so on, up to the end, viz. 52 and 53. The numeral 54 was used to express nondescript patterns.

The finger prints had to be gone through repeatedly, some weeks elapsing between the inspections, and under conditions which excluded the possibility of unconscious bias; a subject of frequent communication between Mr. Collins and myself. Living at a distance apart, it was not easy at the time they were made, to bring our respective interpretations of transitional and of some of the other patterns, especially the invaded loops, into strict accordance, so I prefer to keep his work, in which I have perfect confidence, independent from my own. Whenever a fraternity consisted of more than two members, they were divided, according to a prearranged system, into as many couplets as there were individuals. Thus, while a fraternity of three individuals furnished all of its three possible varieties of couplets, (1, 2), (1, 3), (2, 3), one of four individuals was not allowed to furnish more than four of its possible couplets, the two italicised ones being omitted, (1, 2), (1, 3), (1, 4), (2, 3), (2, 4), (3, 4), and so on. Without this precaution, a single very large family might exercise a disproportionate and even overwhelming statistical influence.

It would be essential to exact working, that the mutual relations of the patterns should be taken into account; for example, suppose an arch to be found on the fore-finger of one brother and a nascent loop on that of the other; then, as these patterns are evidently related, their concurrence ought to be interpreted as showing some degree of resemblance. However, it was impossible to take cognizance of partial resemblances, the mutual relations of the patterns not having, as yet, been determined with adequate accuracy.

The completed tabulations occupied three large sheets, one for each of the fingers, ruled crossways into fifty-three vertical columns for the A brothers, and fifty-three horizontal rows for the B brothers. Thus, if the register number of the pattern of A was 10, and that of B was 42, then a mark would be put in the square limited by the ninth and tenth horizontal lines, and by the forty-first and forty-second vertical ones. The marks were scattered sparsely over the sheet. Those in each square were then added up, and finally the numbers in each of the rows and in each of the columns were severally totalled.

If the number of couplets had been much greater than they are, a test of the accuracy with which their patterns had been classed under the appropriate heads, would be found in the frequency with which the same patterns were registered in the corresponding finger of the A and B brothers. The A and B groups are strictly homogeneous, consequently the frequency of their patterns in corresponding fingers ought to be alike. The success with which this test has been fulfilled in the present case, is passably good, its exact degree being shown in the following paragraphs, where the numbers of entries under each head are arranged in as orderly a manner as the case admits, the smaller of the two numbers being the one that stands first, whether it was an A or a B. All instances in which there were at least five entries under either A or B, are included; the rest being disregarded. The result is as follows:—

I. Thirteen cases of more or less congruity between the number of A and B entries under the same head:—5-7; 5-7; 5-8; 6-8; 7-10; 8-9; 8-12; 9-12; 10-10; 11-13; 12-16; 14-18; 72-73. (This last refers to loops on the middle finger.)

II. Six cases of more or less incongruity:—1-7; 6-12; 14-20; 14-22; 22-35; 39-50.