THE SOUTHERN PLANTER. 



167 



the different analyses. The experiment was insti- i 

 tuted mainly for the purpose of ascertaining the 1 

 quantity of mineral substances which become fix- < 

 ed or converted into an integral part of the animal 1 

 frame in a given time. The amount of organized ' 

 nitrogen assimilated during the same interval, was 

 also ascertained and reported. The subject of the i 

 experiment was a calf 6 months old, in good con- « 

 dition and in full growth, such being the circum- < 

 stances in which the process of assimilation is re- ; 

 garded to be the most rapid and complete. Dur- 

 ing the two days the calf was made the subject of 

 experiment, it ate 19 pounds of hay, having been < 

 supplied Avith this fodder ad libitum for several 

 days previously. In the course of the first day the 

 calf voided 21 pounds of solid excrement, discard- 

 ing fractions, and the second day 20 pounds, mak- 

 ing 41 pounds in the two days; which being drted, 

 was reduced to 7 pounds. During the two da* 5 

 pounds of brine were excreted, the animal having 

 drunk, in the same interval, 45 pints of water. 

 Analysis ascertained in the food consumed, discard- 

 ing fractions, 69 half drachms of nitrogen, and in 

 the solid and liquid excrements together, 54 half 

 drachms. As the hay consumed contained 69 half 

 drachms of nitrogen, and the excretions 54 half 

 drachms of this element, it is clear that the. differ- 

 ence between them (16 half drachms) is the amount 

 of organized nitrogen assimilated, or converted in- 

 to an integral part of the animal organism during 

 the period of 48 hours. Analysis likewise discov- 

 ered 368 half drachms of mineral matter in the 

 hay consumed, and 252 half drachms in the de- 

 jections. The difference between them (76 half 

 drachms) is the amount of mineral substances fix- 

 ed in the body of the calf in the course of two 

 days. 



From this investigation into the nutrition of a 

 calf, it is apparent that a considerable proportion 

 of the organic and inorganic elements of the food 

 is assimilated, and serves, for a time, as an integral 

 part of the mysterious structure. If the animal 

 organism was not endowed with the power of as- 

 similating the elements of nutrition, presented in 

 the various articles of food, no animal would be 

 capable of prolonging its existence beyond a lim- 

 ited period of a very few days. In fact, this is the 

 primary object in supplying them with food, in or- 

 der that they may convert such parts of it as may 

 be adapted to the purposes of nutrition, into an 

 integral part of their organization, and thus make 

 it contribute to their preservation. 



A regular supply of certain substances, (com- 

 monly called animal food,) and a constant supply 

 of oxygen in the form of atmospheric air, are the 

 primary conditions essential to the maintenance of 

 animal life. All the substances contained in ani- 

 mal food are divided by physiologists into two 

 great classes — the nitrogenized and the non-nitro- 

 genized. The nitrogenized substances are the ali- 

 ments proper, and these serve for the nutrition and 

 reproduction of the body. The non-nitrogenized 

 substances serve a very different purpose in the 

 animal economy — that is, they minister to the sup- 

 port of respiration, and they have nothing to do 

 with nutrition, any further than the process of di- 

 gestion converts them into the form best adapted to 

 the support of respiration and the evolution of ani- 

 mal heat. 



The nitrogenized substances are vegetable fi- 

 briue, vegetable albumen, vegetable caseine, and 

 animal flesh. All these nitrogenized products are 

 identical in their composition, and when introduced 



into the animal system, are capable of being con- 

 verted into blood, and the blood thus formed is 

 capable of being converted into muscular fibre, in- 

 to cellular tissue, and into every part of the body, 

 which is the seat of the vital principle. 



The non-nitrogenized substances are starch, gum, 

 sugar, butter, .fat, oil, beer, wine, and the whole 

 catalogue of alcoholic liquors. All these substan- 

 ces are carbonaceous — they are destitute of nitro- 

 gen, and consequently possess no power of nutri- 

 tion. They are designed to subserve a different, 

 though not less important purpose in the animal 

 economy. The carbon which they contain, when 

 introduced into the system in the form of food or 

 drink, enters into combination with the oxygen 

 absorbed into the blood from the atmosphere by 

 the respiratory organs, and fulfils the two-fold pur- 

 pose of supporting respiration and maintaining ani- 

 mal heat. And here, we can but admire the dis- 

 play of creative wisdom by which results so differ- 

 ent and important are accomplished, at one and the 

 same time, by an agent so simple. 



At every expiration, and during every moment 

 of life, a certain amount of carbon is separated 

 from the animal body, and having entered into 

 combination with oxygen, is exhaled into the at- 

 mosphere in the form of carbonic acid. According 

 to the experiments of Boussingault, a milch cow 

 exhales 70| ounces of carbon in twenty-four hours. 

 If this element is not supplied in the food the pro- 

 cess of respiration cannot be sustained, and the de- 

 velopment of animal heat will be arrested. As it 

 frequently happens, that animals are unavoidably 

 deprived of food for a time more or less prolonged, 

 nature has made a temporary provision for the oc- 

 currence of such casualties. This provision con- 

 sists in the fat deposited in the cellular tissue. 

 The carbon of the fat (fat is a compound of carbon 

 and hydrogen) at every inspiration, combines with 

 the oxygen absorbed into the circulation, and the 

 oxydized product, in the form of carbonic acid, is 

 expelled from the system during every expiration. 

 The supply of carbon from this source would soon 

 be exhausted, and then the muscles or fleshy part 

 of the animal would begin to yield up that portion 

 of this element which forms a component part of 

 their structure, in order to furnish support to this 

 vital process, Avhich cannot be suspended, even for 

 a few minutes, without fatal consequences. But as 

 before, the supply of carbon derived from this 

 source is soon consumed, and if food be any long- 

 er withheld, the other organic tissues, whose inte- 

 grity is essential to the maintenance of life, begin 

 to yield up their portion of this element, and this 

 process goes on until the particles of the brain be- 

 gin to be oxydized, and life is extinguished. 



Bodily exercise increases the consumption of 

 carbon, and consequently the demand for food. 

 Every movement of the body, and every emotion 

 of the mind, accelerates the waste of the organic 

 tissues, and consequently mental as well as physi- 

 cal exercise, creates an increased demand for those 

 elements adapted to the reproduction of the animal 

 organism. 



All experience teaches that a regular supply of 

 food is essential to the preservation of life. That 

 an animal has no power to create any one element 

 of nutrition or respiration requisite to preserve its 

 organization, is a fact no less true; and yet it is 

 far less generally recognised. The vegetable or- 

 ganism only, has the power of creating nutritious 

 products; and from vegetables only, every such 

 product is originally derived. In this regard, they 



