PERIODS OF DISEASES. SECT. XXXVI. a. 



he intervals of the exertion of the petforal muf- 

 ,cles. 



2. The following natural animal a&ions are influ- 

 enced by folar periods. The periods of fleep and 

 of waking depend much on the folar period, for we 

 are inclined to fleep at a certain hour, and to awake 

 at a certain hour, whether we have had more or 

 lefs fatigue during the day, if within certain limits ; 

 and are liable to wake at a certain hour, whether 

 we went to bed earlier or later, within certain li- 

 mits. Hence it appears, that thofe who complain 

 of want of fleep, will be liable to fleep better or 

 longer, if they accuftom themfeives to go to reft, 

 and to rife, at certain hours. 



The periods of evacuating the bowels are gene- 

 rally connected with feme part of the folar day, as 

 well as with the acrimony or diftenlion occafioned 

 by the feces. Hence one method of corre&ing cof- 

 tivenefs is by endeavouring to eftablifli a habit of 

 evacuation at a certain hour of ,the day, as recom- 

 mended by Mr. Locke, which may be accomplifhed 

 by ufing daily voluntary efforts at thofe times, join- 

 ed with the ufual flimulus of the material to be eva- 

 cuated. 



3. The following natural animal actions are con- 

 netted with lunar periods, i. The periods of fe- 

 male menftruation are connected with lunar periods 

 to great exaclnefs, in fome inftances even to a few 

 hours. Thefe do not commence or terminate at 

 the full or change, or at any other particular part of 

 the lunation, but after they have commenced at any 

 part of it, they continue to recur at that part with 

 great regularity, unlefs difturbed by fome violent 

 circumftance, as explained in Se&. XXXII. No. 6.^ 

 their return is immediately caufed by deficient ve- 

 nous abforption, which is owing to the want of the 

 flimulus, ciefigned by nature, of amatorial copula- 

 tion, or of the growing fetus. When the catamenia 



returns 



