Sect. XXXIII. i. 4. OF SENSATION. 307 



The fenfitive fevers with weak pulfe, which are termed putrid 

 or malignant fevers, are diftinguilhed from irritative fevers with 

 weak pulfe, called nervous fevers, defcribed in the laft fection, 

 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 petechia?, or 

 purple fpots, and aphthse, or Houghs in the throat, and generally 

 with previous contagion. 



When animal matter dies, as a Hough in the throat, or the 

 mortified part of a carbuncle, if it be kept moift and warm, a 

 during its adhefion to a living body, it will, foon putrefy. This 

 and the origin of contagion from putrid animal fubflances, 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 animalcula - } the urine, if too 

 long retained, may alfogain a putrescent fmell, as well as the 

 alvine feces ; but fome writers have gone fo far as to believe, 

 that the blood itfelf in thefe fevers has fmelt putrid, when drawu 

 from the arm of the patient ; but this feems not well founded ; 

 fmce a fingle 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 j and that hence if the blood was putrid, air fliould 

 be given out, which in the blood-veiTels is known .to occafiorj 

 immediate death. 



In thefe fenfitive fevers with flrong pulfe (or inflammations) 

 there are two fenforial faculties concerned in producing the dif- 

 eafe, viz. irritation and fenfation ; and hence, as their combined 

 action is more violent, the general quantity of fenforial power 

 becomes further exhaufted during the exacerbation, and the 

 fyftem more rapidly weakened than in irritative fever with 

 (trong pulfe ; where the fpirit of animation is weakened by but 

 one mode of its exertion : fo that this febris fenutiva pulfu forti 

 (or inflammatory fever) may be considered as the febris irritativa 

 pulfu forti, with the addition of inflammation j and the febris 

 fenfitiva pulfu debili (or malignant fever) may be confidered as 

 the febris irritativa pulfu debili (or nervous fever, with the addi- 

 tion of inflammation. 



4. In thefe putrid or malignant fevers a deficiency of irrita- 

 bility accompanies the increale of fenfibiiity ; and by this wafte 

 of fenforial power by the, excefs of fenfation, which was already 

 •too fmall, arifes the delirium and ftupor which fo perpetually at- 

 tend thefe inflammatory fevers with arterial debility. In thefe 

 afes the voluntary power firft ceafes to acl: from deficiency of 



fenforial 



