FINAL PRODUCTS. 429 



nutrient power of bone-gelatin and of gelatigenous tissue, afford us 

 sufficient evidence that this nutrient power cannot be concentrated 

 into a single chemical compound, even if it be of a somewhat com- 

 plex nature. 



Accurate quantitative determinations regarding the influence 

 upon the animal organism of food which is insufficient in quality 

 were first instituted by Boussingault, and were specially conducted 

 in reference to certain agricultural points. We have previously 

 alluded to those experiments of this chemist,* by which he demon- 

 strated the importance of salt for the well-being of the organism 

 a fact which has been subsequently confirmed by the researches of 

 Plouviez f and Dupasquier. J The most decisive conclusions in 

 reference to this subject are however afforded by the investigations 

 which have been carried on by Boussingault, Playfair,|| Thomson,^ 

 Payen and Gasparin,** Persozft and others, in reference to the 

 fattening of animals with various kinds of fodder. Since we shall 

 subsequently revert to the influences which most essentially affect 

 the augmentation of the weight (during growth or the process of 

 fattening) we shall here merely give the results (by way of illustra- 

 tion) which Boussingault obtained in his experiments on cows. 

 Potatoes and beet-root alone were insufficient to nourish a cow 

 (that is to say, to retain it at the same bodily weight), even when 

 these kinds of food were supplied to the animal in very great 

 excess. It follows from these, as well as from certain earlier inves- 

 tigations, that every kind of food is insufficient, (1) if it cannot be 

 taken in such large quantities that its nitrogenous matters may 

 serve to replace the organic particles rendered effete by the meta- 

 morphosis of tissue, (2) if its digestible constituents do not contain 

 sufficient carbon to supply the carbon which is lost by the respira- 

 tion and other excretions, (3) if it does not contain sufficient salts, 

 especially phosphates, and, (4) consequently, we find that a certain 

 quantity of fat in the food, notwithstanding the simultaneous pre- 

 sence of carbo-hydrates, if not positively necessary, is yet very 

 desirable in order to retain the organism in a healthy condition. 



It seems placed almost beyond doubt, by these experiments, 



* Ann. de Chim. et de Phys. 3me Ser. T. 19, pp. 117-123. 



t Bullet, de 1'Acad. de MeU T. 14, pp. 1077-1085. 



% Journ. de Pharm. 3me Ser. T. 9, pp. 309-344. 



Ann. de Chim. et de Phys. T. 12, p. 153. 



|| Philosoph. Magaz. Vol. 22, p. 280. 



<ft Trans. Med. Chir. Soc. Vol. 29, pp. 327-340. 



** Compt. rend. T. 18, p. 797. 



ft Ibid. p. 245. 



