Should the accused smooth the hair upon his head with his hand, it is a sign of fear, for he feels a sensation at the roots of his hair as though each particular hair was standing on its end. He therefore involuntarily attempts to smooth it down. Now all this may be true, but it conveys nothing, and to take it as a sign of guilt is childishly absurd. A perfectly innocent person may have a greater sense of fear than the most guilty criminal, for certainly the ultimate consequences of the trial are to him of far greater importance, and more likely to produce the sensation of fear. I have before me the latest addition to this class of book, so far as England is concerned. It numbers no less than five hundred pages, and each page contains at least four hundred words. It comes to us from Austria, via America. Its translation into English must have been a stupendous task, for the author has laid the world under contribution, and given us selections from, and references to, hundreds of books dealing with criminal psychology: the result being an intensely interesting book. Just how far the demeanour, actions and traits of foreign criminals may furnish safe guidance in the judgment of English prisoners, neither author nor translator tell us. But as the peculiarities of crime and criminals are generally questions of latitude and longitude, climate, environment, social condition and national temperament, so it seems to me that the psychology and mannerism of criminals must differ accordingly, and that the rules set up for guidance in one part of the world may be quite inapplicable to another part. The author tells us that this book is a “manual” for judges, practitioners and students; for it deals not only with the psychology of criminals or suspected criminals, but with that of judges, magistrates, witnesses and police also. To every thoughtful layman I would heartily recommend this book, for it is well worth reading and pondering; but I would rigidly prevent all judges, magistrates and jurymen having access to it. Why? Because it is their business and prerogative to decide upon the guilt or innocence of the prisoner according to the weight of the evidence, every detail of which demands their concentrated attention if justice is to be done.