154 Life ana Letters of Francis Galton
impressions, a mistake had been made in the reference number and a wrong dossier was produced. Galton writes
"I wish to point out the moral of this. In every system there must be some clerk-work and a consequent liability, however small, to clerical blunders. In the system by measurements at least five have to be made and recorded for each person, and they each require three figures to
express them. The frequent occurrence of mistakes in this complicated process was the main motive for abolishing measurements altogether, first in India, and now in this country. In the finger-print system all the above clerk-work is done away with because the hand of the accused person prints its own impression. As regards the comparative trustworthiness of the two systems, there can be no reasonable doubt. I took, as you may be aware, great pains in testing them, with the result that it is inconceivable to me that an expert to whom the impressions have been submitted of two different persons, taken with the cleverness that is habitual in prisons, should ever mistake one set for the other."
II. Popularisation of Finger-Printing.
sI propose in this section to give an account of some of the minor papers and letters to newspapers by which Galton made the idea of finger-printing familiar to his countrymen. I think this plan is better than scattering them chronologically between his more solid contributions to the science of the ubject, which will be dealt with in the remaining section of this chapter.
In August 1891 Galton published in the Nineteenth Century (Vol. xxx, pp. 303-311) an article entitled "Identification by Finger-Tips." It contains a resume of his Royal Society papers in a popular form, an account of his apparatus and a suggestion that professional photographers should take up finger-printing as part of their trade. He concludes with the prophecy
"I look forward to a time when every convict shall have prints taken of his fingers by the prison photographer at the beginning and end of his imprisonment, and a register made of them ; when recruits for either service shall go through an analogous process; when the index-number
of the hands shall usually be inserted in advertisements for persons who are lost or who cannot be identified, and when every youth who is about to leave his home for a long residence abroad, shall obtain prints of his fingers at the same time that the portrait is photographed,
for his friends to retain as a memento." (p. 311.)
Another matter in connection with finger-prints which excited Galton's attention and has very considerable scientific interest is the question of scars and wounds as influencing the ridges. On Plate VI are given illustrations of this matter which I have found in the Galtoniana. In Fig. (v) we have an enlarged print of a graft on the bulb of a thumb. In this case J. R. H., a solicitor in large practice, sliced off a piece of the flesh of his thumb; it was promptly picked up, replaced in what was thought to be its original position and the thumb tightly bandaged. The print taken thirty years later shows that the ridges had not been properly adjusted, the orientation of those on the graft being almost at right angles to their true position* !
In ' Fig. (i) a-d we have a good illustration of the effect of a burn, which occurred in the case of Sergeant Randle, Galton's assistant. In Fig. (i) b taken immediately after the accident, the ridges have entirely disappeared, but Fig. (i) d indicates that if the injury has not been too
* See Nature, Jan. 30, 1896 (Vol. LIII, p. 295).