The Scranton tribune. [volume] (Scranton, Pa.) 1891-1910, 1896-11-06

heat for every square metre of surface
or about 2s. horse power OF energy fof
each square metre.
The radiation Of the heat from the sun
is not eternal: y had its beginning ana
IL the sun radiates light and heat in
all directions II cannot be more than lVo.
oo.Oo0 years old. This is Lord kelvin's es-
innate.
At the present rate the sun will con.
tinue from seven to fifteen millions OF
years, but the end will surely come. =,
The actinometer Is one instrument by
which the suns heat Is measured. II
balances the radiation from body at 7
known temperature against a beam OF
sunshine. An allowance has to be made
for the absorption by the earths at
The meldometer and -micrometer
are the instruments used by Wilson ana
Gray in the accurate determinations abov.
referred TO. The principle of the meido-
meter Is the balancing of an electric cur
rent generated by allowing the suns rays
to fall on a thermopile against the eiec.
trio current generated by an incandescent
platinum strip of known temperature act
ing on a similar thermopile.
Attempts have been made to utilize tine
suns heat to do useful mechanical work,
and Ericsson. the Swedish inventor, de-
vised q form of engine in which the rays
were reflected from and concentrated by
curved mirror upon a small pipe hlled
with water, steam being thereby geher-
ated, which was utilized TO drive steam
engine, and furnishing power to run
printing press of two horse power ca
pacity.
1t is suggested that where sunshine may
he depended upon, as in Egypt and other
tropical countries where fuel is scarce,
the Ericsson engine might be CONNER
cially useful.
The sun consists of three parts. the
central portion, or nucleus. which Is gas
eous, but rendered viscous under the enor-
nous pressure and high temperature; the
photosphere of incandescent metallic va
pors, and the corona. which Is only ob-
servable during the time of total eclipse.
Among the elements most character
istic of the sun are hydrogen, the recently
discovered helium and iron.
The corona consists of gas rs yet nm
exist in other stars. 1t is characterized
by a line in the gree spectrum.
Sun spots are comparatively dark
patches upon the suns surface.
1t is believed that the sun spots are
cavities In the surface rendered dark by
some cooling action.
The suns surface is so intensely bright
that an electric light held against il
Sun spots change In structure from mo-
ment to moment
During certain definite seasons of the
year sun spots travel across the suns
definite seasons of the year they travel
across the surface In curves.
Sun spots occur in greater or less num-
hers, new ones forming and old ones dis
appearing constantly. There is a maxi
mum number at periods about eleven
years apart, according to observations
made continuously during the presen GEN.
tury.
Attempts have been made to connect the
outbreak of sun spots with almost every
thing from financial crisis and the price
of wheat to outbreaks Of cholera.
The only real concordance between sun
spots and terrestrial happenings is the
fact that magnetic storms are more nu-
marSable manner with the size and num-
Der OF sun spots.
These magnetic storms and sun spots
may be related to each other. in that
agency, and not by each others agency.