

680 LARD AND ANIMAL FATS 



with silver nitrate, indicating absence of common salt ; 

 and no blue coloration with iodine solution, proving freedom 

 from starch, of which about 20 per cent, is found in some 

 inferior samples ; 10 per cent, of water is sometimes in- 

 corporated ; alum and lime are occasionally added to secure 

 whiteness and increase weight ; while many brands of 

 American lard are largely mixed with cotton-seed oil. 



Benzoated lard, preferable on account of its agreeable 

 odour and diminished liability to rancidity, is made by 

 melting one pound of purified lard over a water-bath, 

 stirring in two hundred and ten grains of benzoin and after- 

 wards straining. Suet the fat around the kidneys of 

 sheep or oxen differs from lard chiefly in being firmer, 

 harder, and more difficult to melt. Horse fat is more easily 

 melted, but firmer than that of swine. Goose grease, much 

 used as a popular remedy for sprains and bruises, is more 

 fluid, from its greater percentage of olein. 



ACTIONS AND USES. Fats and mild fixed oils, when given 

 without other food, are inadequate to support life ; thus, 

 dogs, receiving only butter and olive oil, with distilled water 

 to drink, died in about thirty-six days. In a well-regulated 

 system of diet, fats serve, however, important purposes ; 

 along with albuminoids they form cells ; they build up the 

 nervous structures, so largely composed of fatty matters ; 

 are consumed in the body for the evolution of nervous, 

 muscular, or digestive force, and for the support of animal 

 heat, or, if in excess of these constant requirements, are 

 stored away, investing and protecting internal organs. 

 Fats are emulsified by the alkaline intestinal secretions, 

 more thoroughly dissolved by the bile, and absorbed mainly 

 through the lac teals. Although small doses are easily 

 assimilated, large quantities disorder digestion and cause 

 diarrhoea. 



Hog's lard is occasionally used as an internal demulcent, 

 as an antidote for poisoning with alkalies, and as a laxative 

 clyster. It is applied as a lubricant in exploration of the 

 rectum or uterus, and in cases of difficult parturition. In 

 reducing enlarged joints or bursse by vigorous rubbing, 

 the hand is occasionally moistened with lard to prevent 

 undue skin irritation. When the skin is congested, inflamed, 



