If the patient is sufficiently ill to require the best action of digitalis, an active preparation should be obtained. It was long supposed that the infusion presented activities which could not be furnished by the tincture of digitalis. This seems not to be true. The greater value of the infusion is generally because it is freshly made and active; the tincture which had been used previously in a given case was old and useless; furthermore, most physicians give a larger dose of the infusion than they ever do of the tincture. Owing to the uncertainty of the value of the digitalis leaves found in the various drug shops, however, and to variations in the preparation of the infusion, it is generally better to use a tincture of known character. The beginning dose of such a tincture should generally not be more than 5 drops, and it should not be repeated more frequently than once in eight hours. It is generally advisable, in two or three days, to increase this dose to 10 drops once in twelve hours, later perhaps to 15 drops twice a day, and still later to 20 drops once a day. This amount may then be decreased gradually, if the action is satisfactory. Enough should be given to procure results, and then the dose should be brought down to what seems sufficient and best, administered once a day. The frequence advised in the administration of this drug is because it is eliminated slowly. Its greatest action develops a number of hours after it has been taken, and then the action lasts for many hours; the administration of digitalis once in twenty-four hours is perfectly satisfactory for many patients, and more satisfactory than any more frequent administration. On the other hand, some patients do better on a smaller dose once in twelve hours. This frequence is always sufficient. Digipuratum and digitol, a fat-free tincture, proprietary preparations accepted by the Council on Pharmacy and Chemistry for inclusion in N. N. R., may be employed. They are standardized preparations and may thus be more satisfactory than some pharmacopeial preparations of digitalis, although their claims to lessened emetic action are not borne out by recent experiments of Hatcher and Eggleston. Digipuratum may be obtained in tubes of twelve tablets. The advice has been given for patients with loss of compensation to receive four tablets the first day, three the second, three the third, and two the fourth day. This, however, is generally an overdosage. The most that should generally be given is one of these tablets in twelve hours. Digipuratum fluid is also a valuable preparation. Digitol is a fat-free tincture of digitalis which is physiologically standardized and which bears on each package the date of manufacture. The close is from 0.3 to 1 c.c. (5 to 15 mimims). Digitalinum, one of the active principles of digitalis, is not very satisfactory. It may be given hypodermically, but often causes irritation, and the proper dose and its value are apt to be uncertain.