[Footnote 17: _Jour. Obst., etc._, Aug., 1869.]
The kidneys have been mentioned above. They are often found rather large. Though the fact has been alluded to before, I will here again state that it has always been the general impression that the amount of lime eliminated in the urine of rachitic children is excessive. The reverse of that is true. Seemann and Lander have proved beyond dispute that in most stages of rachitis there is less than the normal amount of lime in the urine. Thus, the theory that lime is eliminated by an excess of acids in the blood is proven to be incorrect. But it is a fact that the rachitical bone contains a proportionately small amount of lime. The conclusion is, then, that its introduction must have been diminished. On the other hand, every article of food contains a large amount of lime, which might be introduced into the circulation if digestion be not at fault. The fact is, that a large amount of lime introduced is not utilized, and is eliminated with the feces.
In connection with these facts the following will be found very interesting. It has been found by Bunge that when potassium, with the exception of chloride of potassium, meets chloride of sodium, the two will exchange their acids, so as to form chloride of potassium and phosphate of sodium. They will be found in the blood also, will be eliminated as such, and result in a comparative absence of chloride of sodium from the serum of the blood. Now, comparative absence of chloride of sodium diminishes the possibility of the development of hydrochloric acid. Thus, it is not a surplus of acid, but a lack of hydrochloric acid, which results from such chemical combinations. If such be the case, calcium salts are not absorbed sufficiently. Thus, they will appear in the feces, and not even be absorbed in the intestines, because of the alkalinity of the intestinal secretion, by which the lime cannot be dissolved. The more lime, then, is introduced under these circumstances, the greater the incumbrance to digestion.
The correct proportion between chlorine, phosphorus, potassium, and sodium is certainly exhibited in woman's milk. There is lime enough in even the poorest article of that kind. But indigestion brought on by { 155} woman's milk in a disordered condition or by any other cause will prevent the absorption of lime when a superabundance of phosphorus and potassium disturbs the formation of hydrochloric acid. In these cases not only the development of the bones, but also that of the muscles, is disturbed. The latter is of great importance in regard to circulation, because a large part of the circulation depends on the pressure on the part of the muscular fibres exerted on the small blood-vessels. These facts have been the reason why I insist upon the addition of chloride of sodium to the food of infants and children, particularly those who are fed on cow's milk; for cow's milk and vegetables contain a relative superabundance of potassium compared with sodium. Even adults will find cow's milk very much more digestible by adding table-salt to it.