SOURCES, DEPOSIT, AND REMOVAL OF FAT. 251 



If, in addition to this state of quiet or rest, sleep likewise be indulged in, 

 the object is still more perfectly attained ; and if a high temperature be 

 resorted to, since this checks the oxidation needful for maintaining the 

 system at its due temperature, this also diminishes the waste of the fat. 



Under such circumstances, where every thing is done to give a supply 

 of fat, and every thing to prevent -its consumption, it may be caused to 

 accumulate in the tissues to an extraordinary amount. But The liver affect 

 this very soon interferes with the action of the liver, one of ed in that oper- 

 the functions of which we have seen is the preparation of fat. atlon ' 

 And it may also be remarked that many of the diseases of that organ, 

 especially those occurring in hot climates, meet their explanation on the 

 principles we are here inculcating, the state of rest produced by lassitude, 

 the warm and therefore expanded air that is breathed, and the improper 

 resort to oleaginous articles of food. 



In view of the preceding facts, it may therefore be concluded that the 

 interior source from which the adipose tissues are supplied Summar of 

 is the fat contained in the plasma of the blood, into which it the sources, 

 has been poured through the thoracic duct, or otherwise ob- ^^and^an- 

 tained from the digestion of food in the small intestine ; and ner of removal 

 since the blood-cells contain a higher percentage of oily ma- 

 terial than the plasma (2.2 per cent, may be extracted from them by ether, 

 either as a phosphorized fat or glycero-phosphoric acid), they constitute 

 reservoirs of supply to meet the exigencies of the system, there being a 

 necessary relation between the quantity they can thus retain in store 

 and the quantity contemporaneously existing in the plasma, a diminution 

 of which at once establishes a drain upon the cells. Thus charged with 

 these hydrocarbons, the plasma passes wherever there are adipose cell- 

 germs, furnishing to them the special nutriment they require for their 

 development 'into fat-cells, the wall and nucleus of which are derived from 

 the blood, or, as we have mentioned, in certain cases actually from the 

 muscular tissues. The amount of fat which can thus be held in reserve 

 depends in part on the number of germs, in part on the supply of fat 

 from the digestive organs, and in part on the supply of appropriate ma- 

 terial for the walls and nuclei. 



When the fat thus stored up is wanted, the cell wall in many cases 

 deliquesces or wastes away, surrendering its contents back to the plasma, 

 but probably much more frequently a transudation of the hydrocarbon 

 takes place through it, analogous to what has been described as occur- 

 ring in the blood-cells themselves. This demand upon the adipose tis- 

 sues may originate for many reasons, since there may be a necessity for 

 fat in the accomplishment of the various histogenetic operations going 

 forward, or for those of retrograde metamorphosis, or for the maintenance 

 of a normal state of the blood as respects its oleaginous ingredient, or for 



