The problems of fatigue have recently, for well-known reasons, attracted unusual attention. They are, however, ancient problems around which a bewildering and contradictory mass of work and literature has accumulated. The author, who has for many years been working on the subject, here deals (in a Presidential Address to the American Psychological Association last year) with one limited aspect of these problems: the relativity of fatigue. He is more concerned with the scientific than with the practical aspects of the subject, for he considers that the extreme practical importance of fatigue has injured its proper scientific investigation. For this we must know what mental fatigue is, if it exists at all, and how it is conditioned.

The writer commences her article by enunciating the doctrine that the normal human being is asymmetrical. “In 1903,” she says, “I expressed the opinion that the normal man is asymmetrical. The principle of the bilateral symmetry of the organism, established until recently in biological sciences, is replaced to-day by the idea of asymmetry, which, far from being an abnormal or pathological phenomenon, is, on the contrary, the expression of the natural state. One of the halves of the body is more developed than the other from an anatomical and physiological point of view. In the case of the right-handed man, it is the right side which is favoured; in the case of the left-handed man, it is the left. Now, each half of the body being dependent on the hemisphere of the opposite side, one sees that in the case of the right-handed man it is the left brain which is most developed, whilst in the case of the left-handed man a greater development of the right brain is assumed.” This thesis is supported by references to the works of many observers.

Sadness, or rather melancholy in the common acceptation of the word (I hardly think the word depression quite conveys the writer's idea), tedium vitó, and impulse, appear to Prof. Del Greco to be the most important elements in the mentality of an individual about to commit suicide.

This study in psychological and forensic medicine is a model of systematic arrangement of facts. Narrative, family history, and biography occupy their proper positions in the perspective, and although one cannot altogether agree with the writer's conclusions, one is filled with admiration for the minute and careful analysis of the physical and mental personality of the criminal.