[March, 
138 
The Heat of the Sun. 
SSSS&ws&isstettvs 
", an* that the “condition of the photosphere,^ ,nd, 
cated to us by the sun-spots, also varies. 1 - , 
posed to be accounted for by the circumstance tha , 
whole solar system is moving through space with h 
citv of 150,000,000 of miles annually, it a PP^ P ~ 
that the condition of the gaseous fuel supp y g ■ on 
may vary according to its state of previous decomposition, 
in whictf other heavenly bodies may have taken subiefted 
Since its first publication this theory has been subject 
to a considerable amount of criticism. Some of this m y 
P aH Hs S c» d dwXwe 0 sh°ail'ha;e to considerably modify some 
O our ideas of physical aftions. Thus, for example, theie 
to the ’ uXtion V what is known as ^soc.atiom 0 the 
breaking up of chemical compounds ^the ^ 
g&rSiSHS 
considered to bring about the inverse change. rn m- 
sneaking of dissociation, viz., temperature and pressure, 
some of the radiant energy from the bun, altnoug 
te 7he' id"? 7 a mfiversaf'atmosphere, which is necessary 
for the pmposes of this theory, although never prominently 
Sir--" 
an^Tho^^tfuVwdter^upon^he'subjedf, including 6 Grove 
c^ttns SLtf 
