70 = J. H. Lane on the Theoretical Temperature of the Sun. 
would lead us to limit the temperature of such clouds of solids 
or fluids, so also it seems difficult to credit the existence in the 
solid or fluid form, at a — temperature than 54,000° Fah. 
of any substance that we know of 
If then we suppose a felliceciacts of 54,000° Fah. , what would 
be the density of that layer of the hypothetic gaseous body 
— has that temperature, and what length of time would be 
at the observed rate of solar radiation, for the emis- 
the greater the densit of” rage layer of 54000° Fah. and the 
hea which a cubie foot of it would 
feeen as itis known to us. The value of ¢ is in that 
asd about 800 feet, and the value of & about 174, ee the 
same as in common air. ese values would e for the 
layer of 54000° Fah. a specific gravity about 06000095 that 
of water, or about one 90th that of hydrogen gas at common 
temperature and pressure, and the mechanical equivalent of the 
heat that a cubic foot of the layer would give oe = cooling 
down under pressure to absolute zero would be about 
9000 foot pounds, whereas the mechanical aeiealess of the 
heat radiated by one square foot of the sun’s surface in one 
minute is about 254,000,000 foot pounds. The heat emitted 
each minute would, therefore, be fully half of all that a layer 
ten miles thick would give out in cooling down to zero, and a 
circulation that would dispose of volumes of cooled atmosphere 
at such a rate seems inconceivable. 
It may possibly appear to some minds that the difficulty 
the photosphere, or its cloudy particles, to be maintained by 
radiation at a a tempe — to —— any extent dower than that 
commence at a temperature many times higher than the 
Fah. which we have pony for the upper eile surface of 
the clouds, and this, as before i pe seems to me i 
extremely fac are Sig 
