OF THE CELLULAR TISSUE. 121 



larly when distended; it is semi-diaphanous. Its powers of 

 cohesion varies ; in some places, as between the muscular fi- 

 brilli, it is simply that of a slightly viscid liquid ; in others 

 again, its resistance is almost equal to that of the fibrous tissue. 

 This tissue is very extensible, and very retractile, as may be 

 seen by inflating it, and making an incision, it then contracts 

 forcibly, driving out the distending air. Its chemical proper- 

 ties have been carefully studied by Bichat. Deprived of wa- 

 ter by dessication, it loses a part of its physical qualities, and 

 acquires new ones; in this state, it is hygrometrical, and re- 

 sumes its original aspect when placed in water, a peculiarity 

 it possesses in common with almost all the organic tissues. 

 Exposed to heat it dries rapidly, becomes crisp, and ends in 

 burning like all the other tissues, leaving, however, but little 

 ashes. It strongly resists decoction, and is dissolved only by 

 long continued ebullition. It putrefies very slowly: to accom- 

 plish the entire decomposition of this tissue, by maceration, re- 

 quires several months, even without renewing the water; it is 

 converted at last into a viscid substance resembling mucilage, 

 and furnishes divers products which rise to the surface of the 

 liquid. Fourcroy considered it composed of gelatin; John 

 detected in it besides, a small quantity of fibrin, and the phos- 

 phate and carbonate of lime. 



146. The intimate nature of the cellular texture, has given 

 rise to a great number of hypotheses. Ruysch supposes it to 

 be entirely vascular; Mascagni, who scarcely mentions it, says 

 it is composed of white vessels; Fontana of tortuous cylinders; 

 others regard it as an expansion of the nerves. The only base 

 we should admit in it, is the cellular fibre or substance, 68, 85. 

 It is traversed by a great number of vessels, and serous vessels 

 particularly; but it should not be considered as wholly consist- 

 ing of them, for it is it that definitely forms the parietes of the 

 extreme vessels. The cellular tissue has canals or cavities pe- 

 culiar to it. They are the little spaces or areolae with which it 

 is hollowed, or that the liquids excavate as fast as they are de- 

 posited in it, and which by their communication make it a 

 spongy and permeable body. Almost all those who have paid 

 particular attention to injections, Haller, Albinus, Prochaska, 



