Z O O N O M I A. 



SECT. L 



OF MOTION. 



JL H E WHOLE OF NATURE may be fuppofed to 

 conlift of two eflences or fubftances ; one of which 

 may be termed fpirit, and the other matter. The 

 former of thefe poffeffes the power to commence 

 or produce motion, and the latter to receive and 

 communicate it. So that motion, confidered as 

 a caufe, immediately precedes every effect ; and, 

 confidered as an effect, it immediately fucceeds 

 every caufe. 



The MOTIONS OF MATTER may be divided into 

 two kinds, primary and fecondary. The fecondary 

 motions are thofe which are given to or received 

 from other matter in motion. Their laws have been 

 fuccefsfully inveftigated by phiiofophers in their 

 treatifes on mechanic powers. Thefe motions are 

 diftinguiftied by this circumftance, that the velocity 

 multiplied into the quantity of matter of the body 

 acted upon is equal to the velocity multiplied into 

 the quantity of matter of the acting body. 



The primary motions of matter may be divided 

 into three claffes, thofe belonging to gravitation, 

 to chemiftry, and to life ; and each clafs has its 

 peculiar laws. Though thefe three claffes include 

 the motions of folid, liquid, and aerial bodies j 



there 



