THE 
JOURNAL OF SCIENCE. 
MARCH, 1885. 
I. THE HEAT OF THE SUN. 
By Ernest H. Cook, B.Sc. (Lond.), A.R.C.S., F.C.S. 
M^Then we consider the magnificence and beauty 
JQy which, under favourable conditions of the atmo- 
sphere, the heavenly bodies exhibit, it is a matter 
of no surprise that the most brilliant and grandest of them 
all should have attracted and rivetted the attention of the 
earliest philosophers. Accordingly we find in the very first 
pages of the world’s written history, under the influence of 
an Eastern Sun, that those Chaldean shepherd astronomers 
speculated as to the constitution and position of the central 
luminary. Long before the enormous distance of the Sun 
was approximately fixed, speculation began to be made to 
attempt to account for the source of the enormous amount 
of heat which is given out by the Sun. The first and most 
unscientific of these theories of the source of the Sun’s heat 
(that of combustion) was propounded before any adtual ex- 
periments had been made as to the exadt amount of heat 
which is constantly given out. Thus attempting to explain 
and account for something which was not known, it is not 
to be wondered at that subsequent discovery and investiga- 
tion have shown the utter inadequateness of this first 
assigned cause of the Sun’s heat. Before we state and 
examine the various theories it is necessary for us to tho- 
roughly understand and appreciate the vastness of the action 
we have to account for. 
VOL. vii. (third series). l 
