PUS. 149 



Thus, for instance, the pus from accidental wounds or ulcerated 

 parts in a phthisical patient presents under the microscope a totally 

 different appearance from that of a typhous subject, whilst that 

 of the latter would in its turn differ essentially from the appear- 

 ance presented by the pus taken from a drunkard or from a 

 patient exhibiting the cancerous dyscrasia ; and this would be 

 observable even in cases in which the suppurative fluids could not 

 be regarded as the ordinary ichor of surgeons. In case these 

 observations should excite a doubt in the minds of those who have 

 been accustomed to examine pus under the microscope, we would 

 simply refer to the fact that the mere size of the linear diameter of 

 a cyto'id corpuscle frequently furnishes a clue to the nature of the 

 fluid from which it was obtained ; thus, for instance, Henle* found 

 that the cyto'id corpuscles in the pus measured on an average from 

 0'004 to 0'005"', that those in the saliva and mucus were somewhat 

 larger, and those in the blood were, on an average, smaller. These 

 differences he ascribes, undoubtedly with much truth, to the dif- 

 ferent densities of those fluids. When therefore we find that the 

 mere density of the blood, on which depends that of almost all the 

 other juices of the animal body, exerts so great an influence, we 

 can scarcely suppose that the other qualities of the blood should 

 exercise no action whatever on the chemical constitution of the pus. 

 We can hardly therefore be accused of adopting any exaggerated 

 or far-fetched view if we regard all analyses of pus, which are 

 unaccompanied by simultaneous analyses of the blood, as devoid 

 of all importance in interpreting a physiological process, or in pro- 

 moting the recognition of the true constitution of normal pus. 

 We have deemed it expedient to make these preliminary remarks, 

 partly to free ourselves from the reproach of having neglected the 

 laborious investigations of former inquirers in our representation 

 of the chemical relations of pus, and partly to prevent, as far as 

 lies in our power, the misapplication of efforts which would be lost 

 to scientific pathology, by being expended on the chemical analysis 

 of objects whose examination can in no way promote the advance 

 of science. 



We have already observed, in reference to the plasma or the 

 germinal fluid of the pus, that it appears to be originally identical 

 with the fresh plastic exudation which we examined from the 

 secretion of a wound. We will here subjoin a few remarks in 

 addition to the relations which we have already described. In one 

 case the secretion was collected from wounds which had been 

 * Haudb. der ration. Pathol. Bd. 2, S. 685. 



