PHYSICAL anv LITERARY. 91 
tranf{parent parts, which renders them in- 
capable of reflecting any colour, How 
can black bodies, folid or fluid, be at the 
fame time opaque? Can light be finally 
ftifled by the refractive powers of the par- 
ticles alone? Or, ought it not rather to 
make its way thro’ the body, if there be 
no reflexion, without any fenfible lofs, al- 
tho’ the feveral rays might iffue in vari- 
ous direCtions? And, may it not be de- 
manded, in like manner, concerning all 
coloured opaque bodies, How all forts of 
light can be ftifled and ftopt within a 
_ body, whofe internal parts are fitted to 
refle@ only one or two cOlours, and trans- 
mit all the reft? | 
QUER. XXI. If the parts and pores of 
pellucid bodies be much lefs than the leaft 
interval between the fits of reflexion and 
traf{miflion ; it is plain, that rays of light, 
entering a part or pore in a fit of tranf- 
miflion, will not be refle&ted at its back 
4 furface : And thus it may be underftood, 
how all rays that enter the firft furface of 
_ atranfparent body continue to be .tran{- 
Mits 
