It will hardly occasion surprise, after what has been said regarding the importance to the body of an adequate supply of mineral salts, that a theory has been enunciated insisting that the cause of all diseases is lack of a sufficiency of saline material in the system. It was originated by Lahmann, who contended that the composition of the blood, both as regards its specific gravity and its corpuscular element, is liable to very great variation. He therefore believed that the blood is the principal medium of inducing predisposition to disease. He affirmed that, as it is formed from food and drink, it is of paramount importance to measure with accuracy the constituents of our daily diet. In his opinion far too much attention is concentrated upon the chemistry of proteins and far too little upon the mineral substances. He drew attention to the fact that plants refused to thrive if the soil be exhausted of its mineral substances, and that dogs and other animals fed upon washed meat, pure starches, fats, and sugar - i.e., food deprived of its saline matters - die after a short time. They would also die even although we added to this diet the inorganic salts of milk in precisely the same proportions as they are to be found in the ash of milk. Yet animals fed exclusively on cow's milk will go on living indefinitely.

He refprred to Bunge's question whether it was possible for the inorganic salts of the milk to be in chemical combination with its organic substances and only capable of digestion in this combination. His rejoinder to this was that the citrates of potash, magnesium, and calcium in cow's milk are not inorganic, but organic or organised salts, and as such subject to the same metabolic changes as the tissues, and it is, therefore, impossible to replace them by chemical salts. He repeated the observation that a food mixture may have precisely similar amounts of proteins, fats, and carbohydrates to another food mixture and yet differ very considerably with regard to the proportion of inorganic substance. He was satisfied that the total amount of food salts contained in the ordinary diet of European nations is not only altogether too small, but the relative proportions of food salts to each other also differ widely from what he categorised as the standard food mixture. He insisted that it is not sufficient to say that the body requires 3 1/2 grams of salts or inorganic substances daily. It is essential to specify how much potash, soda, lime, iron, etc, is required in a well-balanced ration. As there is usually a deficiency of salts in the diet, he suggested that this can be adjusted by adding root and leaf vegetables, salads, and fruits to the ordinary food. In particular he claimed that the quantities of soda and lime in the daily diet are far below the quantities necessary to maintain a healthy existence, whereas the quantities of potash, iron, and phosphoric acid are generally too big. He quite frankly ascribed the prevalence of rickets and bad teeth to the ill-proportioned combination of salts.

Again he contended that anaemia has nothing to do with a want of iron in the blood, because practically any food mixture contains an abundance of iron. The bones and teeth decay because there are too many acids and salts in our food in proportion to the amount of base, hence, not being neutralised, they easily dissolve the osseous substance of the body. He was also an advocate of the theory that in meat quite one-half of the constituents, including, of course, the albumin and food salts, are as good as useless, their molecules being deprived of vitality because, having performed their work in the body of the animal when alive, they are only waiting to be excreted; In vegetables, on the other hand, he declared, these same molecules perform no work, and hence are abounding in vitality. Just what difference he was able to discover in the metabolism of the tissue-cells of an animal capable of locomotion and a plant condemned to a stationary existence he did not presume to say. He considered the addition of chloride of sodium to be unnecessary if we choose our food correctly. It is a stimulant and, like all stimulants, conduces to intemperance. Rice, he insisted, supplies us with too few salts and potatoes with too many, because they compel us to force through the kidneys more than forty times the amount of alkaline salts that rice does, much to the detriment of both stomach and kidneys.

To obviate this defective provision of our food, he supplied a food salt extractive prepared from leaf vegetables, but the experience of those who have placed themselves under his treatment has not convinced me that any notable addition has been made to the practice of scientific dietetics. If he has demonstrated anything at all it is that we should not be content with too restricted a dietary, but our choice should range over a great variety of comestibles suited to the particular season in question.

Moreover, there appears to be nothing very novel either in his theory or his practice, nor can they be said even to have the merit of originality. After his remarks on flesh foods it is to be inferred that he either was a vegetarian or favoured that cult, and Bunge not only points out the necessity for the addition of common salt to such a diet, but was able to procure a sample of a salt obtained by ignition of a plant and used as a seasoning for their vegetarian diet by the negroes near Khartoum. On analysis this salt was proved to contain 19.27 Na2O and 4.92 per cent. K2O.

In lieu of fresh vegetables it is now possible to obtain dried and pulverised specimens of spinach, celery, lentils, etc, so that large quantities of natural mineral salts can be prescribed in an agreeable form; but introduced as they have been by vegetarians, we question whether it might not be fair to retort that their molecules are deprived of all vitality in a manner similar to the flesh of animals.