116 On the Nature and Conftrudtion 
But it is time to profit by the many valuable obfervations ; 
we are now in poffeffion of. A lift of fucceflive eminent 
aftranomers may he named, from Gallileo down to the pré- ~ 
fent time, wlio have furnifhed us with materials for exa- — 
mination. 
In fi upporting the ideas I fhall propofe in this paper, with 
revard to the phyfical conftruction of the fun, I have availed — 
myfelf of the labours of all thefe aftronomers, but have been | 
induced thereto only by my own actual obfervation of the — 
folar phenomena; which, befides verifying thofe particulars — 
that had been already obferved, gave me fuch views of the 
folar regions as led to the foundation of a very rational fy{- 
tem. For, having the advantage of former obfervations, my 
lateft reviews of the body of the fun were immediately di- 
rected to the moft effential points ; and the work was by this 
means facilitated, and contracted into a pretty narrow com. — 
afs. 
The following is a fhort extraét of my obfervations on the 
fun, to which I have joined the confequences I now believe | 
myfelf entitled to draw from them. When all the reafonings” 
on the feveral phenomena are put together, and a few addi-, 
tional arguments taken from analogy, which I fhall alfo add, 
are properly confidered, it will be found that a general con- 
clufion may be made which feems to throw a “coufiderablem 
light on our prefent fubject, 7 
In the year 1779 dere was a fpot on the fun which was 
larce enough to be feen with the naked eye: By a view of 
it with a feven feet reflector, charged with a very high power, 
it appeared to be divided into two parts. The largeft of the” 
two, on the 19th of April, meafured 1'8”,06 in diameter 5 
which is equal in length to more than 31 thoufand miles, 
Both together muft certainly have extended above 50 thou 
fand. . 
The idea of its being occafioned by a volcanic explofic o 
violently driving away a fiery fluid, which on its return would 
gradually fill up the vacancy, and thus reftore the fun, in that 
place, to its former {plendour, | ought to be rejected on many — 
accounts. To mention only one, the great extent of the a | 
