WHEN SCIENCE AVENGES CRIME.

Manawatu Herald, Volume XLIV, Issue 2386, 31 January 1922, Page 4

WHEN SCIENCE AVENGES CRIME.

MARVELLOUS INVENTIONS FOR TRACKING THE LAWLESS.

So many and so wonderful are the methods of detecting crime that it is now almost impossible for a fugitive from justice to escape. This fact is due largely to the invaluable help provided by science; the greatest inventive brains of the world have-concentrated on the pi’oblem for many years. The methods employed by the police have now reached a high state of perfection. Amazingly clever was the method introduced by Bertillon, the great French criminologist, whose scheme of measurements and finger prints has been instrumental in bringing innumerable criminals to book. Since then, science has gone many steps farther, for in a recent case it was shown that a single hair is sufficient clue to the tracking down of a wanted man.

Some years ago such a tiny clue would have been of very little use. Then there was little to learn from it other than the colour of the man’s hair. To-day, the investigator finds it a most important factor, providing numerous details as to the identity of the criminal. THE MICROSCOPE DETECTIVE. Examined through the microscope, the hair may show certain peculiarities; the hairs of different people vary considerably. Apart from colour, they may be coarse, medium, or fine; in shape they may be round or oval; in structure they may be made up of large or small rings. Certain races, too, have hair of a very distinctive type.

If any case of the scalp—such, for instance, as that which causes baldness —is present, the microscopist sees it and notes its significance. When his examination comes to an end he is able to state definitely that the crime was committed by, say, a partially bald man with coarse grey hair of a special type inclined to curliness. But the usefulness of the microscope does not end here; when an arrest is made a comparison between the original hair and one taken from the prisoner’s head will go far to establish Jiis innocence or guilt. Then let us suppose that in his hurried exit the criminal has left a tiny shred of cloth—a few threads only —upon a splinter of wood or a projecting nail. The exact composition of the cloth is discovered with the aid of the microscope, as is the precise amount of wool, silk, and cotton that it contains. Then the quality and nature of the wool and the processes through which it has gone in manufacture are examined.

The shred then passes to the chemist, who determines the character of the dyes used in colouring it. With all this information at their service, the police can frequently trace the manufacturer of the cloth, and through him the tailor who sold the suit.

FINGER -PRINT PHOTOGRAPHS. Even if the latter cannot name his customer, he can often say when he made the suit, which gives an important clue to the whereabouts of the wanted man on a certain date.

The usefulness of chemistry in poisoning cases is well known. It enables us to determine the nature of the poison used, the way in which it was administered, and the amount given. Some poisons are so persistent that their presence can be detected even if the chemical examination is not made for weeks, or perhaps months, after death has occurred.

Although these discoveries are of great value, on occasion hitherto they have proved practically useless. For instance, various clues sometimes have led to the identity of the criminal being discovered, but then, with this knowledge in their possession, the police have been unable to do anything to punish the offender. Why? Simply because the man —or woman —has made good his escape, the while the mystery was being unravelled. Here, once again, science has stepped in to baffle the law-breaker, and an invention has been perfected which bids fair to be the wonder of the scientific study in the matter of criminal detection. By its aid particulars can be sent in a mere flash thousands of miles to bring wanted man to justice. BETRAYED BY THE PULSE. This invention —which is said to be infallible —is a combination of the finger-print system and phototelegraphy, and by its aid fingerprint photographs may be sent over the telegraph or the cable wire just like an ordinary message. The success of .the invention in tracking criminals has been greatly helped by the vast strides made in the finger-print system. So many improvements have been discovered' that one would hardly recognise the original scheme as outlined by Bertillon.

Previously, the method of taking finger-prints was to press the fingers first on to an ink-pad and then on to a sheet of paper. Though better than nothing, it was by no means satisfactory, for the results were often smudgy. The modern detective makes use of X-rays. The subject’s fingers are dipped into a metalic solution and then gently wiped with a soft cloth. In this way the metal is removed from the “ridges”, but allowed to remain in the “furrows” of the fingertips. When the X-ray photograph is taken, the latter show up clear, sharp, distinct lines. As the photograph can be greatly enlarged, the most miute peculiarities are distinctly seen. Another development enables pho-

tograplis to be dispatched over the telephone wire. In a very short time Scotland Yard will be able to ring up Crewe and say: “A man wanted for fraud left Euston for Crewe on the afternoon express. Here is his description, and here are his fingerprints.” The new science of psycho-analy-sis is also being used in the detection of crime. A suspected man is asked a considerable number of questions, most of which have nothing to do with the crime. The time which he takes to reply to each is carefully measured by means of a stop-watch. If he shows marked hesitation whenever questions of a certain kind are put, the investigator knows that he is on the right track and follows up his advantage. Sometimes use is made of an extremely ingenious little machine, which measures the variations in the pressure of the blood. The stopwatch may show nothing at all, for a hardened criminal on his guard is very difficult to catch; he will answer all questions with equal readiness. But his pulse gives him away. IS HE TELLING THE TRUTH? Everyone knows what an effect any form of excitement or of nervousness has upon the heart. Under their influence the heart beats — only for a moment perhaps —more rapidly, and the blood-pressure rises.

The sphygmomanometer, as the instrument is called, registers even the tiniest variation, enabling the investigator to see just which questions or suggestions produce nervousness. It is claimed that by its aid a skilled operator can always tell whether his subject is lying or telling the truth! And so by making use of the services of all branches of science, the forces of law and order maintain an ever-tightening grip upon the enemies of society. A small proportion may escape the consequences of their wrong-doing, but on the whole the number of untraced criminals is a small one. It is continually growing less.