It is generally recognized that progress in the development of any experimental science is more often due to the discovery of new methods than to new and more ingenious applications of old ones. An unending procession of new remedies and new procedures moves across the field of clinical medicine. The wide attention bestowed on Abderhalden's pregnancy test may be cited as a specific illustration of the eagerness with which the medical profession is waiting for new methods. Brugsch's new nitric acid test for syphilis is another illustration. This test will doubtless prove even more alluring to those who have opportunity to try it; for, whereas the Abderhalden test was complicated and admittedly full of pitfalls, this new test for syphilis seems almost ideal in its simplicity. Its lack of "rhyme or reason" will not deter many from trying it. In the science of biochemistry, too, we have had a constant