

A Sketch of a History of Pus. 1 63 



duction of pus on the supposition of a similar deposition 

 from effused serum in abscesses and ulcers. Fordyce ap- 

 plied his chemical science, of which he was a master, on 

 this occasion : — he interpreted all the phenomena of sup- 

 puration by means of the principle of purulent fermentation, 

 which compounds pus from the supposed constituent or 

 elementary ingredients of any kind of animal matter, — 

 muscles, nerves, membranes, blood*, &c. This compo- 

 sition, however, was effected solely by the agency of vital 

 powers acting on such animal matters. Hewson sup- 

 ported by new arguments the doctrine of the production 

 of pus by secretion f. Hunter seems to have convinced 

 the medical public, by his ingenious observations and rea- 

 soning, that pus is a secreted fluid ; and, with the excep- 

 tion that inflammation is essential to its production, his 

 doctrine has been for the last 20 or 30 years generally ad- 

 mitted to be well established J. But the minds of the 

 thinking part of the medical faculty seem to have been still 

 left in an unsatisfied state with regard to the notion they 

 ought to entertain of the substance to be called pus. On 

 account of the few properties of it known, they probably, 

 and very reasonably, apprehended that different things 

 might be denoted by this term; or that things in reality 

 the same might be denoted by different terms, being sup- 

 posed to be different from one another. Accordingly, in 

 the course of the last 40 years, inquiries into the nature and 

 properties cf this fluid have been instituted, and been espe- 



* Van Swieten seems to have entertained a somewhat like opinion :— 

 " Pus non fit in vasis sed extra vasa, in vulnere generatur ab effusis humori- 

 bus, calore corporis fotis et mutatis Si enim pus omne in vulnere haerens 

 linteis carptis mollissimis abstersum fuerit tenui liquido non pure post ho- 

 ram vulneris superficies undique madida apparebit; sed si per viginti 

 quatuor horas emplastro tectum fuerit vulnus, illo ablato pus apparebit. 

 Unde pus fit extra vasa ; sed materies, unde fit, per vasa adfertur."-— Com- 

 mentaria, torn. i. p. 2S0. 



f Pus is found in cavities sometimes without ulceration; — globules are 

 perceived in it like those of milk — the quantity, the time of production, and 

 properties of pus are varied by the state of the constitution, particularly by 

 the passions — purulent matter is only the coagulable lymph altered, chiefly 

 by inflammation, in flowing through secretory vessels. See Experimental 

 Essays, by William Hewson, F.R.S. 1772. 



\ I am unable to state precisely the date of Mr. Hunter's doctrine on this 

 subject ; but I learn from the Dissertation on Pus, by E. Home, esq. F.R.S. 

 1788, that he had delivered it, for many years preceding this publication, 

 in his lectures. Mr. Home states Mr. Hunter's conclusion? 5 " that the ves- 

 sels of the part take on the nature of a gland, and secrete a fluid which be- 

 comes pus."—" Pus is a secreted fluid, at least it is formed from a similar 

 structure of vessels as other secretory- organs from the blood." — "Changes ia 

 the constitution affect the state of the pus, which could not be the case if it 

 were made up of the solids and fluids of the part." For further proofs I re« 

 , fer to the ingenious Dissertation of the author. 



L 2 cially 



