Before I go into the more detailed treatment of sclerosis, I must just touch on the question of tobacco. Nicotine, without doubt, is one of the most powerful raisers of arterial pressure known, but in ordinary smoking very little gets into the system. Tobacco chewing and snuff-taking, both nearly extinct, probably introduce more nicotine into the body. The combustion in cigar smoking is so nearly complete that very little poison remains except on the lips. In ordinary cigarette smoking the combustion is about as complete as in the case of cigars, but, if the smoke is habitually inhaled, the absorption through the bronchial mucous membrane is much greater and, I think, must have an appreciable effect on blood-pressure. As in alcohol, so in tobacco, we must not lose sight of the effect on the general nervous system: on many people tobacco, in moderation, has a distinctly soothing influence, and so leads to a quietude of mind which compensates for any other small evil effect. Used in excess, it certainly weakens both nerve and will power, and often heart power. The first effect in experimental nicotine poisoning is greatly raised blood pressure, but at the end dangerously low pressure, and so we find that the ultimate effect of excessive smoking is a feeble, low-tension pulse that is often irregular. Oliver found that, in ordinary people who were not excessive smokers, tobacco raised the systolic pressure 10 to 15 mm., but that the diastolic was unaffected; the variations between the two thus becoming abnormal. This effect generally subsides in a quarter of an hour after smoking is finished. It follows, I think, that a man with sclerosis should think this out for himself, for he is not in a position to take any unnecessary chances. Of another of our daily habits, it is wise to remember that coffee raises pressure more than tea, and China tea less than Indian.