Gibson, taking up the various factors apparently instrucmental in the causation of cancer, first devotes considerable time to occupational incidence, with a discussion of the probable factors involved in this connection. Following this, he discusses other, more general, factors—inflammation, mechanical trauma, sunlight, x-rays, arsenic, etc. As a connecting link between all these miscellaneous factors, he calls attention to the little-accepted neurotic hypothesis of tumor growth, as one that in his view is of value. Finally, he discusses the increased alkalinity of the blood in malignancy, and goes so far as to suggest the induction of some degree of acidosis as a curative measure.
Gibson's arrangement of his material is not particularly well ordered, and his use of that material as a basis for his deductions would appear at times to be rather fine-drawn. These faults are somewhat excused by the prefatory remarks that the little book is in the