The importance of the study of blood-pressure in pathologic conditions has become generally recognized, but its physiologic variations are hardly of less interest. There are some conditions, not directly pathologic in themselves, but readily made so, in which variations of this factor may have a supreme importance. In an article in the Lancet,1 and abstracted in The Journal,2 Dr. George Oliver describes the periodic variations of blood-pressure, especially its increase, and the factors which produce this increased pressure. He finds that the digestive wave of increased blood-pressure is a predominant one, and that it is only temporarily affected by exercise, temperature, etc. There is a uniform rise after eating of some 12 or 18 c.c. of mercury, as shown by the hemodynamometer; the upward rise is rapid, occurring within an hour or little more, while the decline is gradual, and lasts until nearly the next meal time. Thus