OBSERVATIONS ARD EXPERIMENTS ON PUS» g* 



«uch change Is produced if either the purulent matter, or 

 solution of salts, be diluted; nor is it produced if tlie pus 

 be previously coagulated by caloric : also the inspissated pus 

 is coagulable by caloric as usual. No such inspissation is 

 produced by these salts in mucous sputum, or in muco- 

 purulent sputum, so that undoubtedly it is a criterion as 

 discovered by Mr. Hunter in the case of muriate of ammo- 

 nia, and with other neutral salts, as now manifested. 



4. I er.deavoured to find some easy tests for dibtinguish- and otlicr tests, 

 ing pus from mucus; but I did not succeed with the tan- 

 ning principle; gallic acid; supersulphate of alumina; 



nitrate of silver, and other metallic salts; and as already- 

 said, various acids. They all produced precipitation of 

 these animal matters, but not with observable characteristic 

 differences. 



5. To observe the state in which the matter of pus is sp- State in xrhlch 

 creted, I procured the assistance of Mr. May.nard, the pre- P^s is secrsted. 

 sent house-surgeon of St. George's hospital, and Mr. George 

 jEwbank, v.'ho had been on many occasions essentially ser- 

 viceable in my inquiries. Square pieces of goldbeater's 



skin were applied to various sore legs after carefully re- 

 moving the matter already secreted. 'In five or ten minutes 

 the square pieces being removed, they were found wet with 

 a limpid fluid. In this state they were inspected by the mi- 

 crosccpe, by whicli numerous globules were seen. In tea 

 minutes farther the liquid was no longer limpid but opaque, 

 like purs, ia which the usual spherical particles were seea 

 with the microscope as juft mentioned. 



Supposing objections might be offered on account of the 

 alteration of texture of the skin employed, sauare pieces 

 of glass were also a[)plied. The results were the fame in 

 both trials. The two gentlemen above named, as -veil as 

 Dr. Richard Harrison, and other pupils, who happened to 

 be present, all concurred in the observation, that the lim- 

 pid matter became opaque, and that while limpid it was, 

 like pus, full of spherical particles. 



fTo be concluded in our next. J 



V„ 



