! 
concave, or the inner 
spire res? 
colon 
receive ligift 
other means. 
from the sun, or be lighted by any other n^ans. 
I trust this memoir will clear up all suc 1 1 
tics. 
The diagram below, is intended to show that 
the sun, when on the equinoctial, (being then on 
the real horizon of, or at the ninetieth degree oi 
both poles,) must, from his upper side, shine in 
at the N. polar opening, and from his southern 
hemisphere, shine in at the S. polar opening (ow¬ 
ing- to his volume being much greater than that 
0 f the earth,) independent of refraction; and 
bv admitting a reasonable refraction, his rays 
may enter, as far as about the forty-fifth concave 
degree of latitude, and by reflection produce 
\\o-ht, quite to the equator, from each way :—to 
represent which, I have drawn in the figure, the 
bent ray, which enters farthest betv\ een the 
spheres from each pole. 
A stranger lately accosted me in the street, and 
declared that he believed my theory true, be¬ 
cause, said he, heat always rises, therelorc the 
earth could not continually yield it, as is certainly 
the ease—unless the sun shone in at the poles, so 
as to produce heat within ; and he added that a 
pot of water would not get hot, nor ice readily 
melt, by building a lire over, or on them. Al¬ 
though I do not fully concur in the application 
he makes of Ills position, yet I find reason to be¬ 
lieve, that ail the heat which comes out of the 
earth, has not previously entered th e surface here.' 
jXO. CL EVES SYMMES. 
