In October, 1905, Korotkow, of St. Petersburg, first advocated the determination of blood-pressure by auscultation. His method has been thoroughly studied, especially in Germany, and has been adopted by many observers as a routine procedure. Apparently it has been little, if at all, discussed in American or English literature, and in view of the importance of proving or disproving certain claims which have been made for it, it has seemed advisable to present this preliminary report of a series of observations which have been undertaken, in the hope that others may be induced to gather testimony. The usual manometer and its equipment are employed in the auscultatory method, and the brachial artery is selected for auscultation at a point from two to four cm. below the cuff. The blood-current is shut off in the usual manner and the first sound which is heard, as, with the fall of the