358 PERIODS SECT XXXVI. 3. 10. 



jo. The periods of hemicrania, and of painful epilepfy, are 

 liable to obey lunar periods, both In their diurnal returns, and 

 in their greater periods of weeks, but are alfo induced by other 

 exciting caufes. 



11. The periods of arterial haemorrhages feem to return at 

 folar periods about the fame hour of the evening or morning. 

 Perhaps the venous haemorrhages obey the lunar periods, as the 

 catamema, and haemorrhoids. 



i 2. The periods of the haemorrhoids, or piles, in fome recur 

 monthly, in others only at the greater lunar influence about the 

 equinoxes. 



13. The periods of hsemoptoe fometimes obey folar influence, 

 recurring early in the morning for feveral days ; and fometimes 

 lunar periods, recurring monthly ; and fometimes depend on 

 our hours of fleep. See Clafs I. 2. i 9. 



14. Many of the firft periods of epileptic fits obey the month- 

 ly lunation with fome degree of accuracy ; others recur only at 

 the moft powerful lunations before the vernal equinox, and af- 

 ter the autumnal one ; but when the conftitution has gained a 

 habit of relieving difagreeable fenfations by this kind of exertion 

 the fit recurs from any flight caufe. 



15. The attack of palfy and apoplexy are known to recur with 

 great frequency about the equinoxes. 



1 6. There are numerous inflances of the effect of the luna- 

 tions upon the periods of infanity, whence the name of lunatic 

 has been given to thofe afflicted with this difeafe. 



IV. The critical days, in which fevers are fuppofed to termi- 

 nate, have employed the attention of medical philofophers from 

 the days of Hippocrates to the prefent time. In whatever part 

 of a lunation a fever commences, which owes either its whole 

 caufe to folar and lunar influence, or to this in conjunction with 

 other caufes ; it would feem, that the effect would be the great- 

 eft at the full and new moon, as the tides rife higheft at thofe 

 times, and would be the lead at the quadratures -, thus if a fe- 

 ver-fit mould commence at the new or full moon, occafioned 

 by the folar and lunar attraction diminifhing fome chemical af- 

 finity of the particles of blood, and thence decreafmg their Ulmu- 

 lus on our fanguiferous fyftem, as mentioned in Sea. XXXIL 

 6. this effect will daily decreafe for the firft feven days, and 

 will then increafe till about the fourteenth day, and will ugain 

 decreafe till about the twenty-firft day, and increafe again till 

 the end of the lunation. If a fever fit from the above caufe 

 fhould commence on the feventh day after either lunation, the 

 reverfeof the above circumstances would happen. Now it is 

 probable, that thofe fevers, whofe crifis or termination are in- 

 fluenced 



