DISEASES OF SENSATION. SECT. XXXIII. t . 



The fenfitive fevers with weak pulfe, which are 

 termed putrid or malignant fevers, are diftinguifhed 

 from irritative fevers with weak pulfe, called ner- 

 vous fe'/ers, defcribed in the laft fedion, as the 

 former confift of inflammation joined with debility, 

 and the latter" of debility alone. Hence there is 

 greater heat and more florid colour of the fkin in 

 the former, with petechias, or purple fpots, and aph- 

 thae, or floughs in the throat, and generally with 

 prev o contagion. 



\Vhen animal matter dies, as a flough in the 

 throat, or the mortified part of a carbuncle, if it 

 be kept moifl and warm, as during its adhefion to 

 a living body, it will foon putrify. This, and the 

 origin of contagion from putrid animal fubftances, 

 feem to have given rife to the feptic and antifeptic 

 theory of thefe fevers. 



The matter in puftules and ulcers is thus liable to 

 become putrid, and to produce microfcopic animal- 

 cula ; the urine, if too long retained, may alfo gain 

 a putrefcent fmell, as well as the alvine feces \ but 

 fonie writers have gone fo far as to believe, that the 

 blood itfelf in thefe fevers has fmelt putrid, when 

 drawn from the arm of the patient : but this feems 

 not well founded ; fince a fmgle particle of putrid 

 matter taken into the blood can produce fever, how 

 can we conceive that the whole mafs could continue 

 a minute in a putrid ftate without deftroying life ? 

 Add to this, that putrid animal fubftances give up 

 air, as in gangrenes ; and that hence if the blood 

 was putrid, air fhould be given out, which in the 

 blood-vefiels is known to occafion immediate death. 



In thefe fenfitive fevers with ftrong pulfe (or in- 

 flammations) there are two fenforial faculties con- 

 cerned in producing the difeafe, viz. irritation and 

 fenfation ; and hence, as their combined adion is 

 more violent, the general quantity of fenfoiial pow- 

 er becomes further exhaufted during the exacerba- 

 tion, 



