NATURE OP THE INTERVERTEBRAL SUBSTANCE. 215 



When the fluid is evaporated in a temperature not ex- Analysis of th« 

 ceeding 220° to half its bulk, an opaque substance, in the fl"Ji™\^hr' 

 form of blueish white filaments, gradually separates. A shark. 

 thin semitransparent pellicle forms at the same time upon 

 the surface, which, when removed, is soon succeeded by 

 another. These pellicles were dried on bibulous paper. 



The fluid part, remaining after the separation of the fila- 

 mentous substance and pellicles, afforded a very distinct 

 yellowish cloud with solutions containing tannin. It was 

 somewhat turbid, but did not form any deposit. In other 

 respects, it nearly resembled the original fluid before eva- 

 poration. 



The filaments, which appeared during evaporation, were 

 separated by passing the fluid through a piece of fine mus- 

 lin. They resembled albumen imperfectly coagulated, not 

 only in appearance, but in most of their chemical proper- 

 ties. 



When the fluid began to putrify, a considerable quantity 

 of the same substance separated spontaneously. 



This substance was insoluble in water, and when boiled 

 for a few minutes in that fluid, it became whiter, harder, 

 and more opaque. 



It underwent the same change in alcohol, and when 

 boiled in alcohol, or in dilute muriatic acid, it became still 

 more firm, and appeared like perfectly coagulated albu- 

 men. 



In this state it was soluble in a solution of pure potash, 

 forming a saponaceous compound, which was decomposed 

 by dilute muriatic acid, a white flaky precipitate being form- 

 ed. It possessed the other properties, which Mr. Hatchett 

 has enumerated as belonging to coagulated albumen*. 



When the pellicle, which had formed on the surface of 

 the fluid during evaporation, was nearly dry, it became 

 somewhat tough and elastic; it was semitransparent, and of 

 a dirty white colour. 



dily with water, which is coagulated neither by heat nor acids, and which. 

 does not form a precipitate with solutipjij containing tannin. 



t Vide Phil. Trans. 1800. 



When 



