The Princeton union. [volume] (Princeton, Minn.) 1876-1976, 1915-01-28
He Figured 1t at the Amazing Intensity
of 1861 Degrees centisrade, While
the Latest Estimates Place It at
About $500 Degrees.


heat was 1,669, 300 degrees c.!
In 1887 Sir John Herschel and Pouil-
let devised special instruments for
measuring the solar heat, but at the
very beginning disagreed on funda-
mental question. Pouillet wanted to
estimate that the earth's atmosphere
cut off half the suns heat; Herschel
insisted that it cut off only one-third
Herschel reached the conclusion that
the suns heat was two calories per
square centimeter per minute. Pouil-
let calculated it at 1.7633 calories per
square centimeter per minute This
means that the SUMS rays falling YER
tically upon each square centimeter Of
the earth's surface would be sufficient
~ powerful, if it were not for their
absorption by our atmosphere, to raise
1858 grams of water one degree G..
per minute. This number is what as
tronomers call the solar constant.
Pouillet's figures, IL, were generally
accepted until recently. Forbes by ex-
periments at the top and at the base
of a high mountain calculated that 2.S5
was the correct number. Wolfe made
it 2.54, and Crova asserted that it was
certainly superior to two calories per
square centimeter per minute
The American Langley invented the
bolometer, by means Of which he
measured the intensity of each ray by
the length Of it's wave before entering
our atmosphere. Thus he proved that
the rays of shortest length are those
that are most absorbed. 1t is as if we
placed two red glasses between our
selves and the sun, one representing
senting our own.
The Able Moreux, director of the
Bourges observatory, declares in an
article in Cosmos that if these two at
mospheres were eliminated and we
could see the sun as he really is be
would appear to be brilliant greenish
blue. g..
Langley's calculations placed the So
lar constant at about three. He proved
that scarcely GO per cent Of the suns
rays penetrated to sea level.
Other observers obtained other fig
ures, and at the beginning Of this cen
fury the tendency was to return to
those announced by Herschel and
POuillet.
1t is certain that the earth intercepts
only about one tWo-billionth part of
the actual heat of the sun, but if we
adopt Langley's figure, 3, we find that
the fraction of heat received would be
sufficient to melt annually a layer of
ice 222.D feet thick at the equator of
the earth. The average power receiv
ed from the sun over the entire earth
is equal to 154,464.0 600 kilogrammeters
a year, or one continuous horsepower
for every 1.72 square meters.
The greater part of this heat is used
up in keeping the earth warm; but, ac-
cOrding to Helmholtz, about a thou
sandth part of it is absorbed by ami
mails and vegetables and becomes an
abundant reserve of energy for the
human race.
If we accept the more recent figures.
which are the result of the calculation
of Messrs. Abbott. Fowle and Aldrich
at the Smithsonian institution in
Washington and call the solar constant
two calories per square centimeter per
minute, the results are scarcely less
striking.
If the total heat could be applied to
"a block of ice at o degrees @. as thick
as the earth-S,Oo0 'miles-this would
he entirely melted in a quarter Of an
'hour. All the water thus obtained
would be turned to steam at 100 de-
grees C. III minutes later, the whole
operation from ice ito steam having
taken only two hours and twelve min.
,rtes
The most recent estimate of the tenn
perature of the SUMS surface is be-
tween G,0OO and 1000 degrees ;C.-New
York World
Limited Dissipation.
A small henpecked little man Was
about to take an examination for life
insurance.
"You don't dissipate, do you q asked
the physician as he made, ready for
tests. mot a fast liver or anything
Of that sort?''
The little man hesitated moment.
looked bit frightened, then replied in
a small, piping voice, Il sometimes
chew little gnm."-Collier's Weekly.
Over the Limit.
Husband (reading from his paper)-
Here. they say, is a comet coming to-
ward the earth. travelling at the rate
Of million miles a minute. Wife
(awaking from q doze) Why don't
they enforce the speed laws letter.
Exchange.
Every mans house is his safest