16 



ANATOMY AND PHYSIOLOGY OF 



ADIPOSE OR FATTY TISSUE. 



The adipose tissue is composed of iso- 

 lated cells, which appropriate fatty matter 

 from the blood after the same manner as 

 the secreting cells appropriate the elements 

 of bile, urine, and milk. " The portion of 

 fatty matter separated from the circulating 

 fluid to form adipose tissue, is only that 

 which can be spared from the other pur- 

 poses to which they have to be applied ; and 

 hence the production of this tissue depends, 

 in part, upon the amount of fatty matter 

 taken in as food.* This is not entirely the 



* "Deposition. — In almost all animals that arc healthy, 

 copious food of a nutritive kind, combined with little labor, 

 ■will increase the deposition of fat ; but in the human sub- 

 ject, and, indeed in many quadrupeds, the animal spirits 

 appear to have very considerable influence over this secre- 

 tion. We see numberless examples of people, wlio appear 

 to enjoy the best bodily health, and yet arc constantly 

 meagre, though their food and habits of life tend to an op- 

 posite state ; and we may occasionally observe horses and 

 dogs, particularly circumstanced, in which, from their 

 natural leanness, or poorness upon the rib, something of 

 a mental nature would appear to be operating ; indeed, it 

 is a well known truth, that if you separate a horse of an 

 irritable disposition from others with whom he is accus- 

 tomed to be stalled, he will fall away in condition, in con- 

 sequence of (to use the vulgar expression) fretting from 

 being alone; and so much does tliis act of segregation affect 

 some, that I have known them even refuse their food. 

 Those horses are commonly the fattest that ai"e fed on 

 easily digestible food — such as bruised or scalded corn, 

 roots of a nutritive kind, chopped hay, etc., and that 

 have little or no exercise : a fact well appreciated by the 

 horse-dealer, whose horses arc fine and ft for sale, but in- 

 capable of fatigue. 



Absorption. — Constitutional diseases, generally speak- 

 ing, extenuate the body, and more particularly such as are 

 of the acute or painful description ; hence, the irritation 

 caused by a simple puncture in the foot, will, if it be of 

 long duration, induce a state of emaciation : under which 

 circumstances, the absorbents are supposed to act with more 

 than ordinary eff"ect, and to take up the adeps from the 

 interior of its cells — Percivall. 



case, however, as some have maintained ; 

 for there is sufficient evidence that animals 

 may produce fatty matter by a process of 

 chemical transformation, from the starch or 

 sugar of their food, when there is an unusual 

 deficiency of it in the aliment." Liebig 

 wrrites : " Whatever views we may entertain 

 regarding the origin of the fatty constitu- 

 ents of the body, this much, at least, is un- 

 deniable, that the herbs and roots consumed 

 by the cow contain no butter ; that, in the 

 hay or other fodder of oxen, no beef-suet 

 exists ; that no hog's-lard can be found in 

 the potato refuse given to swine ; and that 

 the food of geese or fowls contains no 

 goose nor capon fat. The masses of fat 

 found in the bodies of these animals are 

 formed in their organism ; and, when the 

 full value of this fact is recognized,it entitles 

 us to conclude, that a certain quantity of 

 oxygen, in some form or other, separates 

 from the constituents of their food, for 

 without such a separation of oxygen, no 

 fat could possibly be formed from any one 

 of these substances." 



The chemical analysis of the constituents 

 of the food of the graminivora shows in 

 the clearest manner that they contain carbon 

 and oxygen in certain proportions; which, 

 when reduced to equivalents, yield the fol- 

 lowing series : 



" In vegetable fibrine, albumen, and cas- 

 eine, there are contained, for — 



120 eq. carbon, 3G eq. oxygen. 

 In starch, 120 " " 100 " 



« cane sugai", 120 " " 110 " 



« gum, 120 " " 110 " " 



" sugar of milk, 120 " " 120 " " 



" grape sugar, 120 " " 140 " •' 



EXAMINATIONS RESUMED. 



CELLUL/Ul MEMBK.VXE. 



Q. What is the principal use of cellular membrane ? 



— A. It is employed in uniting, covering, and defending 

 various parts of the body. 



Q. Does cellular differ from serous or nervous mem- 

 branes ? — A. No, they are all resolvable into the same 

 constituents. 



Q. How does the periosteum differ from the above ? 



— A. It presents itself in a more condensed form. 



Q. IIow do capsules of joints differ from common 

 cellular membrane? — A. They ai'e a modification of 

 it, under a condensed form. 



Q. In what part of the animal does cellular mem- 

 brane exist in greatest abundance ? — A. Immediately 

 beneath the skin ; upon the ribs, and about the breast, 

 and under the jaws, m the scrotum, on the inside of 

 the elbow and tliigh. 



