of an excess of water from their connective tissues. Sodium chloride diminishes the solvent action of water on uric acid and the urates; but potassium salts, on the contrary, do not, they may even increase the action. Although nearly all the medical experience recorded has to do with diseased persons, such cases are instructive; it is only reasonable to suppose, that more than a very small quantity of salt in excess of that natural to the food, is a source of irritation in the body, even of the ordinarily healthy individual. Summary.--Enjoyment of food is dependent upon appetite quite as much as upon the nature of the food. Better a simple repast with good appetite than sumptuous fare with bad digestion. There is indeed a causal relationship between simplicity and health. The savage likes the noise of the tom-tom or the clatter of wooden instruments: what a contrast this is to the trained ear of the musician. Uncivilised man has little enjoyment of scenery or of animal life, except as in respect to their power of providing him with food, clothing or other physical gratification. What an enormous advance has taken place. In the case of the painter, his eye and mind can appreciate a wide range and delicacy of colour. Man has improved on the crab-apple and the wild strawberry. From a wild grass he has produced the large-grained nutritious wheat. Vegetables of all kinds have been greatly improved by long continued cultivation. In tropical and sub-tropical climates, where wild fruits are more plentiful, high cultivation is of less importance than in temperate regions. In sparsely inhabited or wild, temperate and cold regions, in times past, when deer and other animals were plentiful, and edible fruits few, flesh could be obtained at less labour; or such intelligence and industry as is required for the cultivation of fruits, cereals, and other foods scarcely existed. Flesh almost requires to be cooked to be palatable, certainly this much improves its flavour. The eating of flesh tends to produce a distaste for mild vegetable foods, especially if uncooked. In process of time, not only flesh but vegetable foods, were more and more subjected to cooking and seasoning, or mixed with the flesh, blood or viscera of the animals killed. Next, food was manufactured to produce a still greater variety, to increase the flavour, or less frequently to produce an imagined greater digestibility or nutritiveness. Man has taken that which seemed most agreeable, rarely has he been intentionally guided by scientific principles, by that which is really best. Only of late years can it be said that there is such a thing as a science of dietetics; although cookery books innumerable have abounded. Of recent years many diseases have enormously increased, some even seem to be new. Digestive disturbances, dental caries, appendicitis, gout, rheumatism, diabetes, nervous complaints, heart disease, baldness and a host of other diseases are due, in a great measure, to abuse of food.