OF THE ARTERIES GENERALLY. 123 



by absorption ; which is least active at youth ; equal with the 

 arteries in middle life ; and predominates in age. By this 

 wonderful power the roots of the temporary teeth are ab- 

 sorbed ; that their crowns may give way : by this also the 

 gubernaculum testis, having fulfilled its office, is absorbed ; 

 and the thymus gland is likewise removed : it is thus car- 

 tilage is taken up, to make room for a bony deposit when 

 the animal approaches maturity. By the absorbents the 

 fluids as well as solids are continually changing ; being taken 

 up and carried back, but always in a fluid state, into the 

 mass of blood. It is by them that the dead parts are 

 separated from the living in sloughing and ulceration. By 

 the superficial absorbents, even gases are received from 

 without ; the water held in suspension by the atmosphere 

 is thus taken in ; hence grazing horses require little or 

 no water ; more especially if not exposed to the heat of 

 the sun, whereby evaporation or exhalation is promoted. 

 The functional office of the absorbents is most important 

 also in the preservation of life under casualties. Long fast- 

 ing is thus borne ; their capability of displacing the animal 

 oil or marrow from the bones, and the fat from the body 

 generally, is here employed to make up the want. Hyber- 

 nating animals live during their torpidity by a slow absorp- 

 tion of the adipose matter ; thus it is found in the instance 

 of the torpid bear, that, however fat he may enter his 

 seclusion, he returns lean and emaciated. 



To our acquaintance with the power of the absorbents 

 the practice of medicine is greatly indebted ; and although 

 we own few means of lessening absorption, we fortunately 

 have many of increasing it. Mechanical friction is the 

 most active and universal agent in stimulating the absorb- 

 ents ; as the hand-rubbing of horses sufficiently proves. 

 Pressure also increases their action ; thus we bandage 

 the swollen legs ; we girth the bodies of our horses, to 

 promote absorption of the interstitial fluid. Exercise, by 

 swelling the muscles, produces pressure ; and thus exercise 

 will remove swelled legs, and promote absorption generally. 

 Blisters likewise exercise an influence over absorption. 

 A still stronger stimulant is iodine ; which is especially 

 useful in enlargement of the glands. Purgatives and diu- 

 retics, and whatever tends to lower the pulse, promotes 



