iNFr.AMMATioN.] MODERN VETERTNATIT PTlACTfCE. [inflammatk.:?. 



l)cMng snmll, iiiflnmmntion must arise from tlio 

 ju-tion being increased beyond the power. 

 "NV'e onght, tlierefore, in this ease, to diminish 

 tlio action of the neighbourinj:; parts, in order 

 to prevent an extension to a part which cannot 

 bear the eflect of it without becoming diseased. 



PROXIMATE CAUSE. 



Numerous opinions have been entertained 

 upon this subject; but almost every theory lias 

 been built upon the supposition of there being 

 some kind of obstruction in the inflamed parts. 



AViiile the circulation of the blood was un- 

 known, and the hypothetical notions of the 

 power of the liver, in preparing and sending 

 firth the fluid, continued to prevail, it is not 

 astonishing that the theories of so many writers 

 should be imperfect. 



It was formerly supposed that the liver was 

 the centre of the vascular system, from vrhich 

 the blood went forth by day to the extremi- 

 ties, and returned again by night. If, then, any 

 peccant matter irritated the liver, the blood 

 was sent out more forcibly ; and if, at the same 

 time, any part of the body were weakened, or 

 otherwise disposed to receive a greater quantity 

 of fluid from the rest, then a swelling was pro- 

 duced by a flow^ of humours to this place. 

 Fluxions, or flows of humour to a place 

 might happen, either from weakness of the parts 

 which allowed the humours to enter more 

 abundantly, or from the place attracting the 

 humours, in consequence of the application of 

 heat, or other agents. 



The ancient writers who suppose that the 

 blood had very little motion, and that its course 

 could easily be directed or changed, recom- 

 mended heat to some part which was remote 

 from a recent inflammation, by which they 

 imagined that the current of blood was altered, 

 and a revulsion made. A revulsion was also 

 made by raising a tumour in some other part, 

 or giving nature an opportunity of discharging 

 the humours from distant parts, by applying 

 blisters, &c. When blood was drawn from the 

 vicinity of the fluxion, or congestion, the mode 

 was called derivation, which only dillered froni 

 revulsion in the distance to which ttie humour 

 was drawn being less. Our present object is 

 only to trace the leading doctrines which have 

 at different times prevailed, as being the proxi- 

 uiate cause of inflammation. 



From the theories of fluxion and cniigostion. 

 which were quite incompatible with the lawn of 

 circulation of the blood, we turn O'lr attention 

 to the doctrine of obstruction. 



IJy some writers obstruction has been 

 strongly advocated, attributing it to a visciditv 

 of the blood, and also imagining it to occasion 

 a resistance to the circulation in the part 

 aflected ; hence, incri'a>ing it in the other 

 vessels, proving an irritation to the heart, and 

 augmenting the force or attraction of the blood 

 in that part of the vessel which was behind the 

 obstruction, causing heat and pain, ami conse- 

 quently an acrimonious state of the fluids, to 

 be followed, in all probability, by gangrene. 



The viscidity cannot be admitted as a proxi- 

 mate cause of inflammation, because we have 

 no proof, say some authors, that this state 

 ever exists ; for, as they say, " "Were a 

 viscidity to occur, it would exist in the whole 

 mass of blood alike, and could not be supposed 

 to produce only a local disorder." This, how- 

 ever, is not true, for all parts are not so suscep- 

 tible of taking disease as others ; consequently, 

 any poison producing inflammation that may 

 have been taken into the system, may afiect one 

 part, and that only ; and this from the suscepti- 

 bility of the part. 



As for the supposition of the co-operation 

 of an acrimony of tlie fluids, the proportion of 

 the saline matter of the blood has never been 

 proved to be greater in this than in any other 

 state of the body. Even were a general dis- 

 order of this kind to be admitted, no rational 

 explanation of the proximate cause of local 

 inflammation could be deduced from it. 



According to the opinion of one of our best 

 authors, inflammation is to be considered only 

 as a disturbed state of parts which require to 

 be restored to a natural mode of action. In- 

 flammation in itself, therefore, is not to be 

 considered as a disease, but as a salutary 

 operation, the consequence either of some 

 violence, or some disease. Tiie same author 

 further remarks, that the act of iuflammation 

 is to be considered as an increased action of the 

 vessels; which action, at flrst, consists simply of 

 an increase, or distension, beyond the natural 

 size of these. This increase seems to depend 

 on a diminution of the muscular power of the 

 vessels; whilst, at the same time, the elastic 

 power of the artery is to be dilated in the same 



25.3 



