1. CARDIAC TONICS.-Digitalis: There is no drug that can take the place of digitalis in loss of compensation in chronic valvular disease. It acts specifically for good, and it has its greatest success in the valvular lesions that cause enlargement of the left ventricle, on which it acts the most intensely. It also acts for good on the right ventricle. It has but little action on the auricles. This is simply a question of muscle; the part that has the greatest amount of muscle will receive the greatest benefit from digitalis, and the parts that have the least, the least benefit. The heart muscle is somewhat similar to other muscles; when we attempt athletic improvement in any muscle of the body, we "train" by stimulating it moderately at first, and are careful not to overwork it; the object, then, is to train the heart muscle. For this reason large doses of digitalis should ordinarily not be given to overstimulate suddenly an overworked and weak heart. While in some instances it has been declared that digitalis should be rapidly pushed to the full extent and then dropped for a time, careful experience shows that this method is often not tolerated, sometimes does positive harm, and has at times seemed to hasten death. Another valuable activity of digitalis is in slowing the heart by action on the pneumogastric nerves. A dilated heart has lost more or less of its regulating mechanism; this is the cause of its irregularity and its increased rapidity. The action of digitalis in slowing the heart, giving it a longer rest, and preventing it from acting irregularly is of great value. This prolonged rest or diastole of the heart allows the circulation in the coronary arteries to become normal, and the nutrition and muscle tone of the heart improves. Digitalis also increases the blood pressure, not only by improving the activity of the heart, but also by causing some contraction of the arterioles. This feature of digitalis action in arteriosclerosis renders its use sometimes a question of careful decision. The dose of digitalis under such a condition should not be large. It may be indicated, however, and may do a great deal of good, and it does not always increase the blood pressure.