It is exceedingly difficult at times to affirm definitely that an artery, the radial for example, is actually sclerosed. Much depends on the sensitiveness of the fingers of him who palpates, and much upon the relation of the palpated artery to the surrounding, chiefly underlying, structures. In the examination of arteries it is well to inspect the body for the pulsations caused by them. Frequently an exceedingly tortuous artery, such as the brachial, may be seen throughout its whole extent and yet the radial appear little, if any, thickened by palpation. Again the artery of a pulse of high tension which is small in size but full between the beats, may not be as sclerosed as one which collapses and feels much softer. It is difficult to obtain accurate data in regard to the tension in an artery by feeling it with the fingers of one hand. One should use both hands. With the middle finger of the right (left) hand the artery is compressed peripherally, that is, nearest the wrist. The blood is then pressed out of the artery with the middle finger of the left (right) hand, so as to obliterate completely the pulse wave and the two or three inches between the middle fingers are felt with the index fingers. By holding the finger firmly on the artery near the wrist so as to block any wave that may come through the palmar arch by anastomosis with the ulnar artery and by releasing pressure on the proximal middle finger, some idea may be had of the degree of pulse tension. However, no amount of practice can more than approximate the tension and when one is surest that he can tell how many millimeters of pressure there are, he is apt to be farthest wrong when he checks his guess with the sphygmomanometer. Much may be learned from carefully palpating the peripheral arteries, and, as a rule, the sclerosis of these arteries means general arteriosclerosis, although there are many exceptions to this. A more recent method, and one which in the author's hands has been found to be valuable, is that proposed by Wertheim-Salomonson who palpates the artery not with the ball of the finger but with the fingernail. The finger is held so that the nail is perpendicular to the surface of the skin and the artery is felt with the end of the nail. The sensation is perceived at the root and makes use of all the sensitive nerve endings there. In this way it is possible to feel the arterial wall distinctly, and a little practice will enable one to determine whether or not the vessel wall is thickened. It is also possible to determine with a considerable degree of accuracy the diameter of the artery and the size of the wall when the current is cut off by pressure on the proximal side of the artery. It is best to have a firm background when this "fingernail" palpation is used. This may be obtained by palpating the radial artery against the lower end of the radius.