The most hopeful of remedies is _antitoxin_. More lives can be saved by this preparation, if used _early_ and freely, than by any other known remedy. Moschcowitz, in 1900, collected 338 cases, with a mortality of 40 per cent. In many of these cases it was not used early. It is of importance, however, to use it at the very outset, and to repeat its use as soon or as often as may be indicated by any exacerbation of symptoms. In one instance under my observation twenty-three phials of antitoxin were used before muscle rigidity subsided; in another case double this amount was used. Without quoting figures it is safe to say that the former great mortality rate of tetanus has been _reduced at least 50 per cent._ by its use, and that further reduction can be effected by its early and prolonged use. The use of antitoxin nowise takes away the necessity for proper physical care of the laceration or the wound. Every particle of affected tissue should be cut away, all the principles of physical cleanliness adhered to, and proper antiseptics used. When the antitoxin is used in the presence of the disease it should be injected into the spinal canal, as it is known that the cerebrospinal fluid may contain a considerable amount of the toxin and is of itself highly poisonous. Therefore after inserting the needle into the canal it is well to withdraw a considerable amount of the fluid before injecting the antitoxin. If this method is pursued the material is brought into more immediate contact with the anterior horns of the cord than could be effected in any other way. After withdrawing all the fluid that will run through the needle without applying the syringe--probably 150 to 200 Gm.--10 to 15 Cc. of the antitoxin may be slowly injected, the process consuming from three to five minutes. Then a further injection should be made along some of the large nerve trunks, preferably those leading to the part involved. This injection should be made with a finer needle, such as that with which cocaine solution is injected during anesthesia for the prevention of shock. This is a more effective and less serious matter than trephining the skull for the injection of fluid upon the surface of the brain. This may be done while the patient is under the influence of the anesthetic administered for the purpose of giving proper attention to the wound. The antitoxin should be injected into the nerve trunks after their exposure. At the same time it is well to make intravenous saline injections at more than one point. After from twelve to fifteen hours the injection of antitoxin and perhaps of saline solution should be repeated, if necessary, under such light anesthesia as can be produced by ethyl chloride. Recently a substitute for antitoxin has been suggested in an emulsion of brain tissue which has been shown to have a specific affinity for the tetanus toxin. It has been seen that when these two substances have been thoroughly shaken together the toxin