2 1 2 Mr, MoR can's Ohftrtaiiom and Experiments^ &c . 

 jlre leafl refrangible. The obfervations and experiments hi 

 this paper feem to render this theory probable. It is, how- 

 ever, an obje<flion to it, that the lefs refrangibility of rays 

 feems to inaply a lefs force of attra£lion between them and the 

 fubftances which refract them ; but it fhould be confidered,. 

 that, poffibly, the force of cohefion, which unites the rays 

 of light to bodies j may be a different power from that which 

 re frails them. 



