It is of interest to note the important part played by the hand in the modern system for the detection of criminals originated by M. Bertillon, who aimed at establishing the identity of individuals by careful tabulation and classification of data obtained by physical measurements and thumb and finger prints. It has been established beyond doubt that the finger-prints of no two individuals are exactly alike. Moreover, nothing can permanently alter the palmar surface of the terminal phalanges of the digits, so that once a finger-print is registered, its owner can at all future times be identified. Finger-prints, obtained by various means - such as first pressing the finger upon an ink-pad, and then transferring it to white paper - form most valuable clues in identifying suspects.

A photograph may deceive, disguise, may defy detection, time or illness abet the wrong-doer, but the records made by his own fingers remain the same, and are often the surest means of bringing their owner to the doom he might otherwise have escaped.