290 DISEASES SECT. XXXII. 4. i. 



If the deficiency of the ftimulus of heat is very great, the qui- 

 efcence becomes fo general as to extinguiQi life, as in thofe who 

 are frozen to death. 



If the deficiency of heat be in lefs degree, but y-et fo great as 

 in fome meafure to diforder the fyftem, and (hould occur the 

 facceeding day, it will induce a greater degree of quiefcence 

 than before from its acting in concurrence with the period of 

 the diurnal circle of actions, explained in Seel: XXXVI Hence 

 from a fmall beginning a greater and greater degree of quief- 

 cence may be induced, till a complete fever-fit is formed; and 

 which will continue to recur at the periods by wliich it was 

 produced. See Sett. XVII. 3. 6. 



If the degree of quiefcence occafioned by defecT: of the ftimu- 

 lus of heat be very great, it will recur a fecond time by a flight-* 

 er caufe, than that which firft induced it. If the caufe, which 

 induces the fecond fit of quiefcence, recurs the fucceeding day, 

 the quotidian fever is produced ; if not till the alternate day, the 

 tertian fever ; and if not till after feventy-two hours from the 

 fir It fit of quiefcence, the quartan fever is formed. This lait 

 kind of fever recurs lefs frequently than the other, as it is adif- 

 eafe only of thofe of the temperament of aflbciability, as men- 

 tioned in Seel. XXXI. ; for in other constitutions the capability 

 of forming a habit ceafes, before the new caufe of quiefcence is 

 again applied, if that does not occur fooner than in feventy-two 

 hours. 



And hence thofe fevers, whofe caufe is from cold air of the 

 night or morning, are more liable to obferve the folar day in 

 their periods ; while thofe from other caufes frequently obferve 

 the lunar day in their periods, their paroxyfms returning near an 

 hour later every day, as explained in Set. XXXVI 



IV. Another frequent caufe of the cold fits of fever is the 

 defect of the ftimulus of diflention. The whole arterial fyftem 

 would appear by the experiments of Haller, to be irritable by 

 no other ftimulus, and the motions of the heart and alimentary 

 canal are certainly in fome meafure dependent on the lame caufe. 

 See Seel:. XIV. 7. Hence there can be no wonder, that the 

 diminution of diftention, fhould frequently induce the quief- 

 cence, which conftitutes the beginning of fev:r fits. 



Monfieur Lieutaud has judicioully mentioned the deficiency 

 of the quantity of blood amongft the caufes of difeafes, which 

 he fays is frequently evident in difledions ; fevers are hence 

 brought on by great hemorrhages, diarrhoeas, or other evacua- 

 tions^; or from the continued uie of diet, which contains but 

 little nourifhment ; or from the exhauftion occafioned by vio- 

 lent fatigue, or by thofe chronic difeafes in which the digeftion 



* is 



