OBSERVATIONS AND EXPERIMENTS ON PUS. 115 



«pon the coa<yuTation, and perhaps, inspissation, by nnion 

 of nentj-al salts with the opaque oxide. 



9. That as the essential parts are secreted in a limpid state, Selfrcoagu- 

 but presently become opaque, owing to a large proportion .vf^ui "i j 

 spontaneously coagulating, and thus becoming the opaque serum separa- 

 oxide, mixed with the serous liquid, and innumerable spheri- [. ^ '^cre. 

 cal particles (Sect. VII, I, 1,2,3), it seems reasonable to 



infer> that these matters are the self-coagulated lymph of 

 the blood and serum, separated by the secretory organs; 

 which act of secretion determines the subsequent state of 

 aggregation of pus, and the globules are at the same time 

 formed analogously to their formation by other secretory 

 organs. How far they are those of the blood altered by 

 secretion may be determined hereafter. It is a collateral 

 proof of this inference, that very thick pus affords from 

 one sixth to one seventh of exsiccated brittle residue, which, 

 as I have found, is nearly the same proportion afforded on 

 the exsiccation of the buffy coat of inflamed blood ; while 

 very thin pus aiTords on exsiccation from one eighth to one 

 eleventh of brittle residue, which is the proportion to be ex- 

 pected from a mixture of serum of blood and Self-coagulated 

 lymph, as I have ascertained. 



10. That the constant inpregnating saline and earthy Saline ahd 

 ingredients of pus are dissolved in the serous fJuid ; ^'n*^ ai*^ f^'d>niT 

 all separable along with the serum, by ablutions with water, 



from the opaque oxide (1), except a portion of the phosphate 

 of lime. These impregnations are the same as those of 

 serum of blood, and of expectorated mucous matter, viz^ 

 muriate of soda; potash neutralized by animal matter or a 

 destructible acid; phosphate of lime; ammonia neutralized 

 probably by phosphoric acid ; with a sulphate, and traces of 

 some other matters mentioned in my former paper, Tb* 

 proportion of these impregnating sjb ta^ces is as the pro- 

 portion of limpid or serous coagulable fluid, and of course 

 inversely as the proportion of the opaque oxide of pus; but 

 it varies in different cases in given proportions of this oxide, 

 and the limpid fluid. In general, if not always, a given 

 quantity of pus contains a smaller proportion of saline mat- 

 ters than an equal given quantity of expectorated mucou* 

 matter, but a given quantity of the limpid coagulated fluid. 



12 contain* ' 



