The amount of the gastric juice secreted has been variously estimated to be from ten to twenty pints a day in a healthy adult, and by the following table, we find that salt, or rather the chloride of sodium, is present in a considerable quantity. Looking, then, at the immense secretion of the gastric juice, salt is really in continual requisition, making it self-evident that if the supply is not kept up in the same ratio, digestion is retarded, the food passes out of the stomach in an undigested state into the duodenum, and the stomach is consequently overstrained because of the loss of one of its most important constituents; the supply of salt not being equal to the demand. COMPOSITION OF GASTRIC JUICE. Water 994·40 Solid Constituents 5·59 ———— Ferment, Pepsine (with a trace of Ammonia) 3·19 Hydrochloric Acid 0·20 Chloride of Calcium 0·06 Chloride of Sodium 1·46 Chloride of Potassium 0·55 Phosphate of Lime, Magnesia, and Iron 0·12 In a sheep’s gastric juice there is to 971·17 of water, 4·36 of chloride of sodium, showing at once how highly necessary it is for cattle to be supplied with it; a sheep will consume on the average half an ounce of salt daily; that it tends to prevent an outbreak of the rot, I have already drawn the attention of the reader.[54] There is we see 0.20 of _hydrochloric acid_ to 994.40 of water in the gastric juice, though some are of an opinion that it is _lactic acid_; the weight of evidence is decidedly in favour of _free_ hydrochloric acid. Food when it is going through the process of digestion is reduced to a pulp by the solvent properties of the gastric juice, which are due to the presence of the animal matter or pepsine, and the hydrochloric acid; neither of these two constituents can digest separately, they must be together; and they must be in that proportion as we have before us in the preceding table; to act as complete disintegrators and solvents. The general effect of digestion is the conversion of the food into what is called _chyme_; and though the various materials of a meal are entirely dissimilar in their composition, whether they are azotised or nitrogenous, and non-azotised or non-nitrogenous; when they are once reduced to this condition, viz., _chyme_, they hardly admit of recognition.