Sacramento daily record-union. [volume] (Sacramento [Calif.]) 1875-1891, 1883-06-16
HEAT PROM THB SUN.

The Mount Whitney observations show
the sun to be hotter than was supposed
/ The heat received at the esrth's surface is
| probably more by one-half than was esti-
mated by Herschel and Pouillet, and even
materially exceeds the values assigned by
more recent Investigators. It would in
! one year melt crust of ice over the
/ whole sunward half Of the earth six hun
| bred feet thick This is, Of course a state
ment in very round numbers. The scientific
! phrase would be that the suns vertical en-
| ergy could raise the temperature of one
| dram Of distilled water three degrees cen
| tigrade per minute for each centimeter of
| the earth's surface nominally exposed.
! Having supplied US with an increased
amount of heat, the Mount Whitney ex.
/ periments also favor us with new figures
] of intenser heat. The estimates of Her
| schel and Pouillet made the temperature
/ of space pa below the zero of Fahrenheit
The new results carry it down nearly to
| the calculations for the absolute zero the
| absence Of all heat, say minus 459' F. To
! the non. scientific mind the distinction be-
tween such far-down temperature is not
unlike that between the pains of rheuma-
tism and those of gout-the first being as
I
point Of human endurance, the govt giving
one turn more.
J Further, it appears that the direct heat
| ing power Of the sun cannot raise Their
mometer quite so F. above its surround
ings, whatever they may be- II we sup.
pose the whole globe thermometer, and
| without an atmosphere, the sun could
! only heat it so above the cold of space,
| leaving it at about minus 400 f. under full
sunshine. The internal heat of the earth
may be disregarded in these calculations.
| It seems paradoxical to say that, if the
| atmosphere were removed from the earth,
its surface would receive more heat and
| yet be much colder. But this is fact of
the same kind as our experience IN ascend.
ing a mountain. The atmosphere does In
deed cut off a great deal of heat. but on
the other hand IL keeps a great deal of that
which it permits to pass through. When
the air ia heated up Co its retaining capac-
ity an equilibrium Is established To
illustrate: Let us imagine large, empty,
windowless hall, with TWO doors partially
obstructed by Centennial turn. stiles, one
for entry and one for exit A procession
Of 100 persons enters per minute. At first
there IS abundant room few want to come
out At the end Of the second or third
minute perhaps only three people are leav.
| ing for one hundred arriving. After
! longer interval the number OF departing
guests is much greater. At last the hall Is
| crowded to its utmost capacity, and If we
| still suppose leo per minute entering, it
| is absolutely certain that 100 per min
ute must be getting out This final
| condition is one which We may call equi-
hbrium. If the turnstiles of Centennial
pattern record their turning, we can as
certain exactly how many people are In
| the hall st any moment. Now to apply
the illustration to heat bearing rays enter
ing our atmosphere, we may suppose that
| nearly all reach the soil through radiation;
| that ninety per cent. 20 ont through the
regular exit OF convection nine per
cent. squeeze back through the turnstile
by which they entered" Tradition :" and
| one per cent. climb out through the chin
ney OF conduction." It follows that by
merely regulating the turnstiles, by modI-
flying this capacity for selecting and hold
ing rays Of certain wave-iengths, atmos-
| pheres could be constructed which would
keep the planet Mercury cool, or the far
off Neptune comfortably warm. Here Is
a hint for Tomaneers who wish to plant
their dramatis persona In some other
world.
The Allegheny and Mount Whitney OBJ
servatious firmly establish the fsct that
the sun is blue, The particular shade OF
color which it has, if viewed without IN
tervening atmosphere, may be laid down
as that on the border of the blue near the
green, about where the line F appears in
the spectrum. Sad to say, this is not 81
Rsthetic hue it is more like thst re-
ferred to in one of Southey's poems :
You could almost smell birthstone, their
breath was so blue, for he painted the
devils so well. "-[Wm. c. Wyckof, IN
Hsrper's Magazine for June.