CLASS IV. 2. 4. OF ASSOCIATION. 427 



ORDO II. 



Decreased Associate Motions. 

 GENUS IV. 



Catenated with External Influences. 



As the diseases, which obey solar or lunar periods, commence 

 with torpor or inactivity, such as the cold paroxysms of fevers, the 

 torpor and consequent pain of hemicrania, and the pains which 

 precede the fits of epilepsy and convulsion, it would seem, that 

 these diseases are more generally owing to the diminution than 

 to the excess of solar or lunar gravitation; as the diseases which 

 originate from the influence of the matter of heat, are much more 

 generally in this country produced by the defect than by the ex- 

 cess of that fluid. 



The periodic returns of so many diseases coincide with the 

 diurnal, monthly, and annual rounds of time; that any one, who 

 would deny the influence of the sun and moon on the periods of 

 quotidian, tertian, and quartan fevers, must deny their effect on 

 the tides, and on the seasons. It has generally been believed, that 

 solar and lunar effect was exerted on the blood; which was thus 

 rendered more or less stimulant to the system, as described in 

 Sect. XXXII. 6. But as the fluid matter of gravitation per- 

 meates and covers all things, like the fluid matter of heat; I am 

 induced to believe, that gravitation acts in its medium state 

 rather as a causa sine qua non of animal motion like heat; which 

 may disorder the system chemically or mechanically, when it is 

 diminished; but may nevertheless stimulate it, when increased, 

 into animal exertion. 



Without heat and motion, which some philosophers still be- 

 lieve to be the same thing, as they so perpetually appear together, 

 the particles of matter would attract and move towards each 

 other, and the whole universe freeze or coalesce into one solid 

 mass. These therefore counteract the gravitation of bodies to 

 one centre; and not only prevent the planets from falling into 

 the sun, but become either the efficient causes of vegetable and 

 animal life, or the causes without which life cannot exist; as by 

 their means the component particles of matter are enabled to 

 slide over each other with all the various degrees of fluidity and 

 repulsion. 



As the attraction of the moon countervails or diminishes the 

 terrene gravitation of bodies on the surface of the earth; a tide 



