UR1NAUY CALCULI. 439 



might indeed be difcovcrcd, had it not becnpre- 

 vioufly known by confidering the competition 

 of the calculus. But, whether all calculi be of 

 the fume nature, I cannot prefumc to deter- 

 mine. New experiments are ncceflfary to decide 

 this qucilion. 



E c 4 IN- 



