INORGANIC ELEMENTS OF FOOD. 413 



calf, it follows that there is a portion of the mineral substance taken 

 in with the food, which remains definitively fixed to concur in the 

 growth or in the evolution of the individual. In an adult animal it 

 is to be presumed that no such definitive fixation of inorganic prin- 

 ciples takes place, or that it is much less considerable ; that in the 

 dejections and several secretions oujzlit to be found the whole of the 

 phosphoric acid, of the lime, &c., taken in with the food. And this 

 presumption is confirmed by experience ; for on instituting an inquiry 

 into the matter upon a horse, it was found that the mineral matters 

 assumed were almost exactly balanced by those discharged. Never- 

 theless, and granting this to be quite true, which it is, it would be a 

 grave mistake to suppose that an adult animal could go on for ever 

 a very short period of time upon food that contained no mineral 

 matter. Precisely as in the case of organic matter, it appears that 

 a portion of inorganic matter is also fixed in the living frame, where 

 for a time it forms an integral element in the wonderful structure ; 

 and a supply of the latter kind is undoubtedly no less necessary than 

 is the supply of the former description recognised by all the world. 

 Were there an inadequate quantity of phosphoric acid, of lime, &c., 

 in the food, no question but that the body w^ould speedily feel the 

 effects of the deficiency, and that disease and death would by and by 

 put an end to life. So much, indeed, seems demonstrated by tho 

 very interesting experiments of M. Chossat, in which he kept 

 granivorous animals upon a diet rich in azotized principles and in 

 starch, but deficient in lime. From some previous inquiries, M. 

 Chossat had observed that pigeons even require to add a certain 

 proportion of lime to their ordinary food, the quantity naturally con- 

 tained in which does not suffice them. Whsat, as we have seen, 

 though it contains a large proportion of phosphate of magnesia, con- 

 tains very little phosphate of lime ; and pigeons put on this grain, 

 though they do perfectly well at first, and even get fat, begin by and 

 by to fall off. In from two to three months, the birds appeared to 

 suflTer from constant thirst ; they drank frequently ; the foeces be- 

 came soft and liquid, and the flesh wasted, and in from eight to ten 

 months the creatures died under the effects of a diarrhoea, which 

 M. Chossat attributed to deficiency of the calcareous element in the 

 food. And it is neither uninteresting nor unimportant to observe, 

 that the same thing occasionally occurs in the human subject during 

 the period when the process of ossification is usually most active. 

 But one of the most remarkable features of M. Chossat's experi- 

 ments was observed in the state of the bones of the pigeons ; they 

 became so thin and weak that they broke during the life of the birds 

 with the slightest force.* The conclusion from this fact is obvious. 

 Supplies of all the elements of all the parts of the body are indispen- 

 sable to the maintenance of health, to the continuance of life. 



A pigeon will eat about 463.140 grains of wheat per diem, con- 

 taining 9.725 grains of ash, in which analysis discovers 4.569 grains 

 of phosphoric acid, and 0.277 of a grain of lime. But this smali 



* Chossat, in Comptes Rendus, t. xiv,, p. 451. 



35* 



