A CHINESE BANK NOTE, 1898
My readers may accept it that the ink used was the same Indian ink with which the Chinese characters on the note were written. That is the unhesitating judgement of such an expert as Mr. Galton, who examined it. The difference between a water ink and printer's ink for identification is enormous. Blood on the fingers has occasionally left impressions that fortunately sufficed to reveal the murderer; but, as a rule, wet fingers leave only smudges as useless as this one. It is quite certain, therefore, that no one in the habit of impressing his thumb-mark as this banker did, would use water ink, if he depended on recognizing it as his own. In short, the smudge on the bank-note was placed there in order to identify the two parts of a piece of paper after severance, not to prove who placed it so. My readers may see what exquisite delicacy of detail can be obtained by printer's ink, when so desired, if they will examine a fine skin impression with a magnifying-glass; even the pores along the ridges can be seen as white dots. For practical purposes, however, such extreme delicacy as this is not needed.
This difference of ink suggests a further remark. The Chinese have used printer's ink for ages. If they aimed at identification they would surely have discovered its great value for clear impressions, and its use could never have died out. On the other hand, a method of identification depending on water ink could never have survived for such strict work as our finger-prints. On the palm of the hand it can give a fairly good impression for such simple identification as is wanted (say) for passports, because the large creases will obviously be those of the bearer of the passport, or as obviously not. These lines of the palm, so well known in palmistry, are as clear to a man as the shape of his hand, while those on the pads of his own fingers are scarcely noticed even now by one man in a million. The science of identification by means of the pads cannot, in my opinion, date farther back than 1858, when I happened to use oil-ink, which was not used for tep-sais.
The ablest defence of the claims of antiquity that I have seen is by a Japanese writer, Kumagusu Minakata, whose letter to 'Nature', Dec. 27, 1894, appears to be as exhaustive as it is able; but I hope that this paper will satisfy him that the finger-print system of our day has no connexion with the methods he describes. The 'nail-marks' of which he speaks must be utterly useless for identification; yet he treats all manner of impressions alike, and tells us indeed that they are all known by the one name of 'hand-mark'. I fear that he has failed, like some other writers,[9] to see the definite force of the word 'identification' in the finger-print system. It means that if a man can be indicated whose finger-print agrees with that on a document, he is identified with the man who put that one there. That is all we want. But it will be seen that there must be two impressions at least, that will bear comparison, to constitute 'identification'.
None of the writers who have undertaken the defence appears to perceive this need of a second impression if the issue of identity turns on any kind of finger-mark. Repudiations cannot have been rare; tribunals must occasionally have been invoked; yet no instance is quoted of decision by demand for a second impression.
It seems then that these marks were not made, as ours are, expressly to challenge comparison; that, in fact, they offer no points for comparison.
In conclusion, it is hard to believe that a system so practically useful as this could have been known in the great lands of the East for generations past, without arresting the notice of Western statesmen, merchants, travellers, and students. Yet the knowledge never reached us.
FINIS.
FOOTNOTES
[1] Till 1857 the East India Company's College.