“But of what value are these imprints,” asked Tarzan, “when, after a few years the lines upon the fingers are entirely changed by the wearing out of the old tissue and the growth of new?”
“The lines never change,” replied the official. “From infancy to senility the fingerprints of an individual change only in size, except as injuries alter the loops and whorls. But if imprints have been taken of the thumb and four fingers of both hands one must needs lose all entirely to escape identification.”
“It is marvelous,” exclaimed D’Arnot. “I wonder what the lines upon my own fingers may resemble.”
“We can soon see,” replied the police officer, and ringing a bell he summoned an assistant to whom he issued a few directions.
The man left the room, but presently returned with a little hardwood box which he placed on his superior’s desk.
“Now,” said the officer, “you shall have your fingerprints in a second.”
He drew from the little case a square of plate glass, a little tube of thick ink, a rubber roller, and a few snowy white cards.
Squeezing a drop of ink onto the glass, he spread it back and forth with the rubber roller until the entire surface of the glass was covered to his satisfaction with a very thin and uniform layer of ink.
“Place the four fingers of your right hand upon the glass, thus,” he said to D’Arnot. “Now the thumb. That is right. Now place them in just the same position upon this card, here, no—a little to the right. We must leave room for the thumb and the fingers of the left hand. There, that’s it. Now the same with the left.”
“Come, Tarzan,” cried D’Arnot, “let’s see what your whorls look like.”