356 Mr. Francis Gallon [May 25, 



specimens cut by a microtome, say of one two-thousandth part of an 

 inch in thickness, and one-tenth of an inch each way in area, out of 

 the 4000 cubic inches or so of the flesh, fat, and bone of a single 

 average human body, there are many that are visible with or without 

 the aid of a lens. 



The markings in the iris of the eye are of the above kind. They 

 have been never adequately studied except by the makers of artificial 

 eyes, who recognise thousands of varieties of them. These markings 

 well deserve being photographed from life on an enlarged scale. I 

 shall not dwell now upon these, nor on such peculiarities as those of 

 handwriting, nor on the bifurcations and interlacements of the super- 

 ficial veins, nor on the shape and convolutions of the external ear. 

 These all admit of brief approximate description by the method just 

 explained — namely, by reference to the number in a standard collec- 

 tion of the specimen that shall not differ from it by more than a 

 specified number of units of unlikeness. I have already explained 

 what is meant by a unit of unlikeness, and the mechanical means by 

 which a given set of measures can be compared with great ease and 

 by a single movement with every set simultaneously, in a large 

 standard collection of sets of measures. 



Perhaps the most beautiful and characteristic of all superficial 

 marks are the small furrows, with the intervening ridges and their 

 pores, that arc disposed in a singularly complex yet regular order on 

 the under surfaces of the hands and the feet. I do not now sj^eak of the 

 large wrinkles in which chiromantists delight, and which may be com- 

 pared to the creases in an old coat, or to the deep folds in the hide of 

 a rhinoceros, but of those fine lines of which the buttered fingers of 

 children are apt to stamp impressions on the margins of the books 

 they handle, that leave little to be desired on the score of distinctness. 

 These lines are found to take their origin from various centres, one of 

 which lies in the under surface of each finger-tip. They proceed from 

 their several centres in spirals and whorls, and distribute themselves 

 in beautiful patterns over the whole palmar surface. A corresponding 

 system covers the soles of the feet. The same lines appear with little 

 modification in the hands and feet of monkeys. They appear to have been 

 carefully studied for the first time by Purkinje in 1822, and since then 

 they have attracted the notice of many writers and physiologists, the 

 fullest and latest of whom is Kollman, who has published a pamphlet, 

 * Tastapparat der Hand ' (Leipzig, 1883), in which their physio- 

 logical significance is fully discussed. Into that part of the subject 

 I am not going to enter here. It has occurred independently to 

 many persons to propose finger-marks as a means of identification. 

 In the last century, Bewick, in one of the vignettes in the ' History 

 of Birds,' gave a woodcut of his own thumb-mark, which is the first 

 clear impression I know of, and afterwards one of his finger-marks. 

 Some of the latest specimens that I have seen are by Mr. Gilbert 

 Thomson, an ofiicer of the American Geological Survey, who, being 

 in Arizona, and having to make his orders for payment on a camp 



