[ 20 } 
ceeded by a facula, or more fulgid appearance, 
the place, which it occupied, is foon after not dif- 
tinguifhable from any other part of the fun’s furface.. 
This' is certain from the accounts of all ob- 
fervers. 
QJJ ERIE S and CONJECTURES, 
tending to explain the above properties of the fpots. 
When vve confider, that the folar fpots, fome of 
whofe properties have juft now been enumerated, 
are fo many vaft excavations in the luminous fub- 
ftance of the fun, and that, wherever fuch exca- 
vations are found, we always difcern dark and ob- 
fcure parts fituated below; is it not realbnable to 
think, that the great and ftupendous body of the 
fun is made up of two kinds of matter, very dif- 
ferent in their qualities ; that by far the greater 
part is fo 1 id and dark ; and that this immenfe and 
dark globe is encompafled with a thin covering of 
that relplendent fubifance, from which the fun 
would feem to derive the whole of his vivifying 
heat and energy ? And will not this hypothecs 
help to account for many phenomena of the fpots 
in a fatisfaflory manner? For if a portion of this 
luminous covering were by any means difplaced, 
fo as to expofe to our view a part of the internal 
dark globe, would not this give the appearance of 
afpot? In this cafe, would not that part of the 
dark globe, which is now laid bare, correfpond to 
the nucleus, and the Hoping fides of the luminous 
matter to the umbra? And is not this confonant 
to that property of a fpot mentioned in the firft 
atticle ; 
