ON THE LAWS OF NATURE. 375 



fubftance of light, of fire and heat ; in fhort, all mat- 

 ter active of itfelf. 



On this matter he makes the very juft remark : that 

 it always tends, from the central point, to the circum- 

 ference, i. e. acts with expanfive force ; whereas, rude 

 unorganifed matter tends from the circumference to 

 the central point, i. e. the law of gravity, or the at> 

 tractive power. 



The directions of thefe two powers are opponte to 

 each other, but they preferve the equipoife, without 

 ever disturbing it. From the combination of thefe two 

 conftantly active powers, all the phaenomena in the 

 world refult. It fhould even feem as if the expanfive 

 power may be repelled by that of attraction. 



All the powers of matter are dependent on one fole 

 primitive power. 



It is very eafy to conceive, that attraction is changed 

 into repulfion, as often as bodies come fo very near 

 together as to feel a friction or a reciprocal fhock. 



After feeing the little that BufFon has delivered on 

 this head, it would not be amifs to read the Theoria 

 philofophise naturalis of pere Bofcovitch, the ragufan 

 geometer, who, as Bettinelli, the mathematician at 

 Parma, once wrote to Algarotti, has fhewn to demon - 

 fbation the neceffityof a repullive power in nature. 



Bofcovitch, in the paffage where he treats of the 

 tranlition of attraction into repuMon, proves, repulfi- 

 ones ejufdem effe feriei cum attractionibus, a quibus 

 dirFerunt tantummodo ut negativum a pofitivo. Even 

 this active power of the element, which mews itfelf by 

 attraction, is. in the leaf! diftances, in minimis diftar>« 

 tiis, repellent 



B b 4 The 



