Dr. Reik is a man of high standing in the medical profession. His opinion is clear and unmistakable and it is presumed he has seen thousands of cases of nose and throat diseases and knows what he is talking about. Dr. Reik refers to the question of so-called smokers' cancer. Cancer is a disease which attacks all kinds of people and may occur in widely different parts of the body. The causation of this disease is not known to the medical profession but what is known about it is that it usually occurs on the site of some previous injury. Thus cancer may occur on the tongue as the result of the constant irritation of a jagged broken tooth. Dr. I. C. Bloodgood (Boston _Medical and Surgical Journal_, No. 2, 1914), who has examined 200 cases of lip cancer says that smoking is a common factor, the disease when occurring being usually on the site of a neglected and ulcerated smoker's burn. The burn may be a charring of the skin due to a very hot pipe stem or burning cigar stem. He says, moreover, that if the burn is not continued and there is no other injury, this defect may heal without evidence of ulceration. Similarly a cancer may be the result of continual use of a broken or rough pipe stem or from using a dirty pipe stem on a broken skin. All these are clearly matters which the average smoker easily and usually avoids. It is, however, clear that tobacco itself is in no way responsible for cancer, and no responsible medical writer on the subject alleges that it is. Most of the medical writers who have inscribed injurious physical effects on the nervous system, heart and sense organs, to excessive tobacco smoking have stated that these effects are due to the toxic action of the alkaloid nicotine known to exist in tobacco. There is a wide difference, however, in the results obtained by different writers as to the amount of the nicotine in tobacco which finds its way with the tobacco smoke. Moreover, some of the investigators who have done very careful work do not consider that nicotine is the toxic element, but the substance called pyridine which is derived from it. Dr. Bush (quoted below) referring to this matter says: "From a review of the literature it would appear that extensive studies had been made as to the effects on living organisms of the alkaloid, nicotine. From such studies a great number of writers, especially laymen, have adopted the hasty conclusion that tobacco smoking entailed like results.