. XXXII. 6. DISEASES OF IRRITATIO^. 433 



nerves, we fliall ceafe to be furprifed, that 

 fo minute a diminution in the gravity of the par- 

 ticles of blood fhou}d fo far affect their chemical 

 changes, or their ftimujating quality, as, joined with 

 other caufes, fqme.tirnes to produce the beginnings 

 of difeafes. 



Add to this, that if .the lunar influence produ- 

 ces a very fmgll degree of quiefcencq at firft, and 

 if that rcjcurs #t certain periods even with lefs 

 power to produce quiefcence than at firft, yet the 

 quiefcence will daily increafe by the acquired 

 habit a6lingat the fame time, till at length fo great a 

 degree of quiefcence is induced as to produce 

 phrenfy, canine madnefs, epilepfy, hyfteric pains 

 or cold fits of fever, inflances of many of which 

 are to be found in Dr. Mead's W9rk on this f ab- 

 ject. The folar influence alfo appears daily in fe- 

 yeral difeafes; but as darknefs, filence, fleep, and 

 our periodical meals mark the parts of the folaf 

 circle of actions, it is fometimes dubious to wliich 

 of thefe the periodical returns of thefe difeafes ar$ 

 to be afcribed. 



As far as I have been able tp obferve, the pe- 

 riods of inflammatory difeafes obferve the folar 

 day ; as the gout and rheumatifm have their greateft 

 quiefcence about noon and midnight, and their ex- 

 acerbations fome hours after ; as they have more 

 frequently their immediate caufe from cold air, in- 

 .anition, or fatigue, than from the effel of luna- 

 tions : whilft the cold fits of hyfleric patients, 

 and thofe in nervous fevers, more frequently occur 

 twice a day, later by near half an hour each 

 time, according to the lunar day ; w hi 1ft fonie fus 

 of intermittents, which are undifturbpd by medi- 

 cines, return at regular folar periods, and others 

 at lunar ones ; which may, probably, be owing to 

 the difference of the periods of thofe external cir- 



cumftances 



