Personal Identification and Description 



173 



cases of triplicated numbers. In other words the index number alone would 

 not suffice to identify an individual in about a quarter of the indexed cases. 

 Now if the index contains 100,000 instead of 100 individuals, it is clear 

 that these multiple cases, instead of being counted by twos and threes, would 

 be counted by hundreds, and the number of references required to the prints 

 themselves would become most fatiguing. The source of this evil is fairly 

 clear if we examine Galton's Table II (p. 548). It classifies the patterns that 

 occur in 100 prints of left forefingers. It is obvious that we have gained very 



Forefinger of Left Hand. 



little indeed in the case of primaries and whorls by taking the nature of the 

 slope as a characteristic. The four groups of 26, 23, 21 and 20 still remain far 

 too large. We need to break up the primaries into three nearly equal groups, 

 not into two of 26 and 4; the same applies to the whorls, while each group 

 of loops requires bisecting. This would give us ten classes, and fit in well with 

 a ten-figure index number. The scheme of indexing Galton proposed in this 

 paper could not be final, yet it was pioneer work*; no one but our author 

 himself had so far published or even suggested a plan for indexing, and there 

 still remained much spade-work to be done before an adequate scheme was 

 evolved. Galton himself recognised the difficulty, thus he writes: 



"The greatest difficulty in constructing a uniformly efficient catalogue lies in the troublesome 

 frequency of plain loops, so that even the method of picture writing fails to analyse satisfactorily 

 the numerous 555, 555, 55, 55 cases. When searching through a large number of similarly indexed 

 prints for a particular specimen, it is a very expeditious method to fix on any well-marked 

 characteristic of a minute kind such as an island, or enclosure, or a couple of adjacent bi- 

 furcations, that may present itself in any one of the fingers, and in making the search to use 

 a lens or lenses of low power, fixed at the end of an arm, and to confine the attention solely to 

 looking for that one characteristic. The cards on which the finger marks have been made may 

 then be passed successively under the lens with great rapidity. I fear that the method of 

 counting ridges (as the number of ridges in All of my previous memoir [see our pp. 163, 167]) 

 would be difficult to use by persons who are not experts. Anyhow, I have not yet been able to 

 devise a plan for doing so that I can recommend." (p. 547.) 



* The diagrammatic symbols used by Galton are the basis from which his fuller classification 

 in Finyer Print Directories starts (see our pp. 199 et seq.). 



