[ 127 ] 



XVI. Practical application of the Law poitited out by Dr. R. 

 D. Thomson, of the proper Balance of the Food in Nutri- 

 tion. By Dr. C. Remigius Fresenius, Professor of Che- 

 mistry at the Agricultural Institute of Wiesbaden*. 



IN reference to the question concerning the relation which 

 must subsist between the nitrogenous and non-nitrogenous 

 nutritive substances in the food oi men and animals, it is but 

 due to Dr. R. D. Thomson to acknowledge, that he considers 

 this the most important circumstance in nutrition, and was 

 the first to call attention to it. 



This relation is obviously different in various classes of 

 animals, and besides it must be different even in the same class 

 of animals, according to their mode of life and to the amount 

 of exercise they undergo. 



An animal which is hard worked will require a different 

 proportion to one which stands at rest in a stable ; still 

 more different must be the proportion when our object is to 

 fatten the animal. I consider it to be one of the most im- 

 portant tasks of dietary and the feeding of cattle, to fix the 

 requisite proportions suited to the various modes of life, for it 

 may be understood that these limits cannot be overstepped on 

 either side without injury. 



Let us suppose, for instance, an animal requires under cer- 

 tain circumstances the proportion of 1 nitrogenous (nutritive) 

 to 5 non-nitrogenous (calorifiant) constituents in its food ; but 

 if we give it food in which the proportion of 1 to 10 prevails, 

 there will be, in the process of nutrition, for every 1 part 

 nitrogenous only 5 parts non-nitrogenous assimilated ; the 

 other half of the non-nitrogenous (calorifiant) aliment will be 

 wasted t. 



But it is not the pecuniary loss alone which arises through 

 this, that deserves consideration ; for it is clear that the animal 

 will be burdened with the process of getting rid of the unas- 

 similated half; for this object strength is required, which 

 might otherwise have been spared. 



If we give it food containing too large a proportion of nitro- 

 genous aliment, in favourable circumstances it will consume 

 the dearer instead of the cheaper non-nitrogenous aliment; 



* Translated from the Lehrbnch der Chemiefiir Landwirthe, Forstmdnner 

 und Cameralisten vo7i Dr. C. Remigius Fresenius (1847), page 480, by Wil- 

 liam Augustus Perston. 



t The original passage is "So wird es beim Ernahrungsprocesse auf je 

 1 Thl stickstofFhaltige eben doch nur 5 Thle stickstoffreie Besthandtheile 

 verwenden, die andere Halfte der slickstofFhaltigen Nahrungsmittel wird 

 vergeudet." The true reading it is apprehended ought to be stickstoffreie 

 Nahrungsmittel, and it has thus been rendered in the English version. — Trans. 



