The Chicago Police Bureau of Identification is the second largest in the world, and contains over 70,000 pictures. [Illustration: Trunk Measurement, Head Length Measurement, Left Middle Finger Measurement, Right Ear Measurement. Measurement of the Stretch and the Left Foot. The Bertillon System of Identification by Measurement.] By combining the Bertillon measurements with the finger-print system the police department has woven a network of identification around the criminal which makes it practically an impossibility for him ever to disguise himself should he at any future time fall into the hands of the officials of the law. [Illustration: (Fingerprint form)] The finger print method was discovered about forty years ago by Sir William Herschell, then an English official in India. Sir Francis Galton, a Fellow of the Royal Society, was the first to systematize it, and the first to establish the fact that the papillary ridges of the fingers did not change through life. This was nearly twenty years ago. Sir Francis Galton made the calculation that the chance of any two sets of finger prints being the same is one in 16,400,000,000, and as an article from which the writer quotes states, "there are only 1,600,000,000 people in the world," its population would have to be increased ten times before two people were identical and means that a finger print as a mark of identification is practically infallible. PERFECTED IN LONDON. Sir Edward Henry, Chief Police Commissioner, London, England, is the man who perfected the system, as it is now used, classifying finger prints by signs and numerals, so that it is now considered perfect. The finger prints of women are the same as men, except in size, while the prints of negroes are the clearest and strongest, owing to the thickness of skin and moisture from perspiration, and it has not yet been demonstrated that finger prints are any indication of character. While quite a large number of cities and penal institutions in the United States have adopted and are now using the Bertillon system of criminal identification, it is to be regretted that it has not been more generally adopted by all cities of a population not less than 5,000, and by all penitentiaries, reformatories and county jails. Universally applied under competent instructors, nearly every professional criminal would, in a few years, be recorded, so that it would only become necessary to keep up with the new additions to the ranks of the criminal classes. It has been thoroughly established that the papillary ridges of fingers never change during life. From infancy to senility and until long after death no change ensues in the fingers. Though partially destroyed by injury, the original lines retain their pristine characteristics when healed.