212 Mr BOWDOIN on an all-furrouniling Orb, 
ance, arc, perhaps, not lefs than our whole dolar yem; and! 
that in them it fhould. fcem. there is-perpetual-unintertupted. 
day. 
| m thefe phenomena it feemg not improbable, ‘thatthe 
Milky Way, and thofe lucid.fpots; are parts of a concave body or 
orb, of the fame nature with {fome of the other heavenly bodies ; 
and, whofe light, tranfrnitted to-us, exhibits: thof phenomena,- 
according to the laws and’ circumftances,. which regulate it. 
- "There is another, and ftill more remarkable phenomenon,. 
that fuggefts the idea of fuch= = Imean the blue con^ 
cave expanfe, which furrounds,.and appears to limit-itble nat 
ture ; and which is the laft to be confidered.. 
It is thus explained by Sir Teac Newton ;: who-obíerves, 
** thatall'the vapours; when they begin to condenfe and coal- 
eíce into natural particles, become firft of fuch a bignefs as to 
refle&t the azure rays, ere they can conititute clouds of any other 
colour. This, therefore, being the firft. colour they begin to 
refet, muft. be that of the finet and moft tranfparent fkies ; 
in which the vapours are not arrived to a groffnefs fufficient to 
reflect other colours."* |. — | 
By this explanation it appears, that the caufe of this pheno- 
menon exifts within the earth’s atmofphere. If it really doth 
exift within it, the phenomenon, from the afligned caufe of it, 
feems to be nothing more than a blue tranfparent cloud, more 
or lefs extentive, in proportion as the atr phere may happen 
to be lefs or more charged with other clouds. 
- XE this were the caue, would not the heavenly bodies, in 2 
clear thy, partake of the colour of that cloud, and appear blue, 
or be tinged with it, by means of their light paffing through 
the 
* Chamberi’s Cydopzdia, under the word Blucaefs, 
E 
oe 
