1891.] Metliod of indexing Finger- Marks. 545 



in efficiency to one that is based on only six, namely, upon the first 

 three fingers of both hands. In the 100 different sets there are 83 

 varieties of pattern in the one case and 65 in the other, which roughly 

 accords with the relative efficiency of 5 to 4. When all the 289 cases 

 are similarly treated, the relative efficiency comes out as 213 to 139, or 

 roughly as 3 to 2. This is a little better but not much. It is, there- 

 fore, a fair question whether it is worth while to impress all the 10 

 digits. The chief advantage of doing so is to add to the volume 

 of evidence, and to supply data which mutilation, or bad scars, or 

 obliteration due to some exceptional cause might render of value. We 

 also see from Table III that the three fingers of both hands are more 

 than twice as efficient for the purposes of an index as those of one 

 hand only ; again, that three fingers are nearly twice as useful as 

 two. I may mention that for my present inquiries into racial and 

 hereditary patterns I am, for various reasons, dealing only with the 

 three first fingers of the right hand, and slightly rolling the fore- 

 finger, so as to obtain a full impression of its pattern on the side of 

 the thumb. 



The greatest difficulty in constructing a uniformly efficient cata- 

 logue 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 one well-marked characteristic of a 

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

 bifurcations, 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 the AH of my previous memoir) would be difficult to use 

 by persons who were not experts. Anyhow, I have not yet been able 

 to devise a plan for doing so that I can recommend. 



