368 



Of the Substances of Animals. 



Voj.. VIII. 



as the wisest, and as good as the best, thus 

 wrote to Washington, more than fifty years 

 ago. " There is some reason to apprehend 

 that masts and sliip-timber will, as cultiva- 

 tion advances, become scarce, unless some 

 measures be taken to prevent their waste, 

 or provide for the preservation of a sufficient 

 fund of both." And this passage has the 

 more weight, since it occurs in a letter de- 

 voted to the suggestion of measures neces- 

 sary to be brought forward for the good of 

 the country. — iV. American Revieio, April, 

 1844. 



Of the substances of Avhich the parts of 

 animals consist. 



The bodies of animals consist of solid and 

 fluid parts. 



The solid parts are chiefly made up of the 

 muscles, the fat, and the bones. 



The muscles, in their natural state, consist 

 in 100 parts of about 



Dry matter, 23 



Water 77 



so that, to add 100 lbs. to the weight of an 

 annnal in the form of muscle, only 23 lbs 

 of solid matter require to be incorporated 

 with its system. 



When the muscular or lean part of beef, 

 mutton, &c., is washed in a current of water 

 for a length of time — the blood, to which 

 the red colour is owing, and all the soluble 

 substances gradually disappear, and the mus 

 cle becomes perfectly white. In this state, 

 with the exception of some fatty and other 

 maiters which still remain intermixed with 

 it — the white mass forms what is known to 

 chemists by the name of fibrin. This name 

 is given to it because it forms the fibres 

 which run along the muscles and constitute 

 the greater portion of their substance. 



When dried beef is burned it leaves about 

 four and a half per cent, of incombustible 

 ash — or 100 lbs. of the muscle of a living 

 animal in its natural state, contain about one 

 pound of saline or inorganic matter. 



Of this inorganic matter, it is of import- 

 ance to know that about two thirds consist 

 of phosphate of lime. Thus to add 100 lbs. 

 to the muscular part of a full grown animal, 

 there must be incorporated with its substance 

 about 



Water 77 lbs. 



Fibrin, with a little fat 22 — 



Phosphate of lime f — 



Other saline matters i — 



100 



The fat of animals consists, like the fat 



of butter, of a solid and fluid portion. The 

 fluid fat is in great part squeezed out when 

 the whole is submitted to powerful pressure. 



The fluid portion of the fat, called by 

 chemists oleine, so far as it has yet been ex- 

 amined, appears to be identical in all ani- 

 mals. It is also the same thing exactly as 

 the fluid part of olive oil, of the oil of alm- 

 onds, and of the oils of many other fruits. 

 It exists in larger quantity in the fat of the 

 pig thiin in that of tlie sheep, and hence 

 pork fat is softer than beef or mutton suet. 

 From lard it is now expressed on a great 

 scale in the United States of America, for 

 burninof in lamps and for other uses. The 

 manufacturers of stearine candles express it 

 from beef and mutton fat, but chiefly for the 

 purpose of obtaining the solid part in a harder 

 state, that it may make a more beautiful and 

 less fiisible candle. The fluid oil of animal 

 fats, however, is known to differ from the 

 liquid part of butter {butter-oil) and from 

 the fluid part of linseed and other similar 

 oils which dry, and form a kind of varnish 

 when exposed to tlie air. These latter facts 

 are not without their importance. 



The .<!olid part of the fat of animals is 

 known to vary to a certam extent among 

 different races. Thus the solid fat of man 

 is the same with that of the goose, and with 

 that which exists in olive oil and in butter. 

 To this the name of margarine is given. 

 But the solid fat of the cow, the sheep, the 

 horse, and the pig, difl^ers from that of man, 

 and is known by the name of stearine. 



The solid and fluid parts are mixed toge- 

 ther in diflxjrent proportions in the fat, not 

 only of diflferent animals, but of the same 

 animal at different periods, and in different 

 parts of its body. Hence the greater hard- 

 ness observed in the suet than in other por- 

 tions of the fat of beef and mutton, and 

 hence also the different quality and appear- 

 ance of the fat of an ox according to the 

 kind of food upon which it has been fed or 

 fattened. 



The bones, like the muscles, consist of a 

 combustible and an incombustible portion, 

 but in the bones the inorganic or incombus- 

 tible part is by much the greater. To the 

 organic matter of bones the name of gelatine 

 or glue is given, and it can be partly ex- 

 tracted from them by boiling. The propor- 

 tion of gelatine which exists in bones, varies 

 with the kind of animal — with the part of 

 the body from which the bone is taken — and 

 very often with the age and state of health 

 of the animal, and with the way in which it 

 has been accustomed to be fed. It is greater 

 in spongy bones, in the bones of young ani- 

 mals, and probably also in the bones of such 

 as are in high condition. In perfectly dry 



