Besides excess of work and unwise work there is another cause which seems to raise pressure, and that is absorption of ptomaines or of the products of imperfect digestion; the overstrain cause and the absorption cause very often act concurrently, for imperfect assimilation is often the result of the unwise life. We see this more often, perhaps, where the unwise life is accompanied by overeating and injudicious alcoholic stimulation, even if this is not very excessive: such people rarely give themselves time to digest. The supply of nerve energy that is necessary for perfect digestion is turned off at the main long before its proper time. We doctors have a first-hand personal knowledge of this cause, for owing partly to the intensive nature of our work and partly to the exigeant importunity of our patients, we more often practise the vices we deplore than the virtues we praise; this is one of the reasons that our profession is the shortest-lived of all. It is not quite clear how this absorption causes hypertension, but it is probably through an effect on endocrine glands, chiefly perhaps on the suprarenal and secondly on the thyroid. McGarrison has shown how often Graves’ disease is caused by faulty intestinal digestion, and by the colitis that ensues; this he thinks stimulates the thyroid to overactivity or to faulty secretion. The suprarenals are probably affected still more than the thyroid, and the hyperthyroidism may be due to the upset of the balance of power; for these two glands through the sympathetic act and react on one another. It is fairly established that in some cases of Graves’ disease we get hypertension and in some hypotension, though both conditions vary a good deal. It may be that the hypotension cases are those that are accompanied by suprarenal deficiency and that benefit by suprarenal treatment, and I believe it to be so. This would explain the conflicting opinions as to the value of this treatment. It has certainly succeeded admirably in some cases. The co-ordination of all endocrine actions is so intricate that we can only puzzle out the way by careful clinical observation and experiment. In sclerosis, as a rule, we get evidence of hyperadrenalism and more certainly of hypothyroidism. Victor Horsley considered premature senility to be a form of myxœdema, which of course means pronounced hypothyroidism.