What infectious diseases has the patient had? Even the exanthemata may cause degenerations in the arteries, but, as has been shown, such lesions probably heal completely with no resulting damage to the vessel. Should the patient have passed through a long siege of typhoid fever the problem is quite different. Here (vide supra) (Thayer), the palpable arteries do appear to be sclerosed permanently. Probably the length of time that the toxin has had a chance to act determines the permanent damage to the vessel wall. More potent than all other diseases to cause early arteriosclerosis is syphilis, and hence very careful inquiry should be made in regard to the possibility of infection with this virus. Not only the fact of actual infection but the duration and thoroughness of treatment are important matters for the physician to know. What is the patient's occupation? Has he been an athlete, particularly an oarsman? Has he been under any severe, prolonged, mental strain? Is he a laborer? If so, in what form of manual labor is he engaged? Such questions as these should never be overlooked, as they form the foundation stones of an accurate diagnosis, and early, accurate diagnosis, we repeat, is essential to successful therapy. We have called attention to the factor of sustained high pressure in the production of arteriosclerosis. Constant overstretching of the vessels leads to efforts of the body to increase the strength of the part or parts. The material which is used to strengthen the weakened walls has a higher elastic resistance than muscle and elastic tissue, but a lower limit of elasticity, and is none other than the familiar connective tissue. In athletes, laborers, brain workers who are under constant mental strain, and in those whose calling brings them into contact with such poisons as lead, there is every factor necessary for the production of high tension and consequently of arteriosclerosis. Another question in regard to personal habits is how much tobacco does the patient use and in what form does he use it? Our experience is that the cigar smoker is more prone to present the symptoms of arteriosclerosis than the cigarette smoker, the pipe smoker, or the one who chews the tobacco. A very irritable heart results not infrequently from cigarette smoking but such is almost always found in young men in whom the lesions of arteriosclerosis are exceedingly rare. The probabilities are that the arteriosclerosis in cigar smoking results from the slowly acting poison which causes a rapid heart rate with an increase of pressure.