MicrocrapHia: 
_ fide BC, and you hall perceive bright red Ring to. appear, cans'd bir 
_ the refraction ofthe Rays, A A A A, which Me dee Or the Globe. ey 
_ which Experiment, ifthe Glafs and,Water be very cleer, fo that there be 
no Sands nor bubbles in the Glafs, nor dirt in the Water, you fhall not. 
_ perceive any appearance of any othercolour.. To apply which Ex peris 
ment, we may imagine the Aimafphere to be a great tranfparent Globe. 
which being of a fubftance more denfe then the other, or Cwhich comes. 
to the fame) that has its parts more denfe towards the middle, the Sun 
beamsthat are tangents, or next within the tangents of this Globe,will. 
__ bestéfracted or inflected from their-direét paflage towards the'center of 
theiGlobe, whence, according tothe Jaws of refractions made ina trian: 
gular Prifw, and the generation of colour fet down in the defcription of 
Mufcovi-glafs,there mutt. neceflarily appeara xed colour in the tranfitas 
or paflage of thofe tangent Rays»,'To make this more plain, we will fup- 
pofe (in the fixth Figure) ABCD, to reprefent the Globe of the i 
mofphere, EF GH to reprefent the opacous Globe of the Earth, lying 
inthe midft of it, neer:to which, the parts of the Air, fultaining a very 
great preflure, md stp very much: condens'd, from whence thofe 
Rays that are by infl€ction made tangents to the Globe of the Earth,and 
thofe without them, that pafs through the more condens‘d part of the Af- 
F mofphere, as fuppole between A and E, are by reafon of the inequality 
of the medinm, inflected towards the center, whereby there mult necef 
farily be generated a red: colour,,as ismore plainly hewn in the former 
cited place ; hence whatfoever opacous bodies. (as vapours,or the like.) 
{hall chance to be elevated into thofe'parts,will reflect a red towards the 
~eyes.and therefore thofe evenings and mornings appear reddeft,that have 
the moft ftore of vapours and halituous fubftances exhaled to a tonve- 
nient diftance front the Earth; .for thereby the. inflection is made the 
greater,and thereby the colour alfo the more intenfesand feveral of thofe 
exhalations being opacous, reflect feveral of thofe Rays, which, through 
an Homogeneous transparent medive would pafs unfeen; and therefdre we 
fee, that when there chances to be any clouds fituatéd in thofe Regions 
they reflect a {trong and vivid-red.' Now, though one great eaufe af 
the rednefs may be this inflection,yet I cannot wholly exclude the colour 
of the vapours themfelves, which may have fomething of rednefs in them, 
-they. being partly nitrous,and partly fuliginous 3 both which fteamstinge 
the Rays that pa throughthem, as is made evident by looking at bodies 
through the pegeiror. oh Hae or Spirit of Nitre.,[as the newly menti+ 
oned Inftrious Perfon has demonftrated} and: alfo through the: of 
a Fire or Chimne ys Said) 2AT I F20iF% ee: sérit of, M3501 TO HnOF nu 
Having thereforemade it probable at leaft, that the a apt 
evening rednefsmay paitly proceed from this-infleétion or refraction 
de. ed. mae Herat ey Gu ob t 37300 agsrioss tae 
~ Suppofe we therefore, EF GH in the fixth Figure of the 37-Scheme, 
to reprefent the Earth ABCD; the Aiméperes E I,.and Ek, two Bay’ 
coming from the Sup, the one from the uppertheother fromthe mea ay 
the Rays,we fhall next thew, how the Oval Figure will be like wie eafily 
229 
