A HISTORY OF THE THEORY OF EDEMA.

The history of the theory of edema shows a striking similarity to the development of the theory concerning secretion and absorption. The latter theory, however, has gained a firmer basis at an earlier time, and the research pertaining to secretion and absorption has shown the way to that concerning edema. The two theories traveled almost identic paths until, through the work of Ludwig and Haidenhain, the theory of secretion and absorption reached pretty firm ground, leaving the solution of the question regarding the production of edema in the rear. Much less good work has been done on the theory of edema during the time following the publication of Cohnheim's first investigation in 1877. Indeed, the theory of edema has been a neglected problem, if we may judge by the few papers which have been published on this subject during the last six years. Still, within the last months, the theory