C 294 3 
XVI. Observations and Experiments on Pus . By George 
Pearson, MlD. F.R.S. 
Read July 5th, 1810. 
Chemical writers vary in their statements of the properties 
of pus ; and they consider that a further investigation is 
requisite for the purposes of science. Physicians confess that, 
in numerous cases, they cannot form a satisfactory judgment 
of the nature of diseases, on account of not being able to 
determine what is, and what is not purulent matter ; likewise 
probably, on account of the existence of different kinds, or va- 
rieties, at least, of this substance, afforded by different disorders. 
I beg leave, therefore, to submit to this learned Society, 
my own observations, experiments, and reasoning on this 
animal matter. 
Section I. Simple , and obvious Properties. 
The different kinds of fluid, commonly considered to be 
pus, may be distinguished by the following titles : 
I. The cream-like and equally consistent. 
II. The curdy and unequal in consistence. 
III. The serous and thin kind. 
IV. The thick, viscid or slimy. - 
I. A pint of the first sort was taken out of the pericardium, 
after a fatal inflammation of the heart, in St. George’s Hos» 
pital, and obligingly sent to me by my colleague, Dr. E. N. 
Bancroft, 
