The new Northwest. [volume] (Portland, Or.) 1871-1887, 1872-02-23
Warmth From the Stars.

1t would scarcely be thought by most
persons says our contemporary that
the stars supply the earth with an APP
preciable amount of heat. Even on the
darkest and clearest night, when the
whole heavens seem lit up by multi
tude of sparkling orbs, the idea of heat
is not suggested by their splendor. IL
will, therefore, seem surprising to many
that men of science should assign no in
considerable portion of our terrestrial
| heat supply to those distant twinkllng
lamps. Ii is not many years since Pro-
fessor Hopkins, of Cambridge, went even
further and expressed his belief That II
the earth's atmosphere were but IN
creased some $4,000 yards in height, so
rs to have an increased power OF retain
| ing the warmth poured upon II from
outer space, we might do without the
sun altogether. so far as our heat supply
is concerned. AS a glass house collects
the suns heat and renders it available
during the time that the sun IL below
the horizon, so he held that the addl-
tional LAYER of air would serve TO garner
the warmth of the stars in quantities
sufficient for all our requirements. But
until lately all these views, however
plausible they might have seemed, had
not been founded upon facts actually
observed. 1t has been reserved for these
days in which discoveries of the most
unexpected kind are daily rewarding
the labors of our physicists to see that
established as a certainty which had be-
fore been founded merely upon consider
ations of probability. Mr.. Higgins, the
physicist and astronomer, has just pub
lished the results of series of inquiries
addressed to the actual measurement of
xr-hfg1a raaaiNa from the
leading brilliants of the nocturnal sky.
The instrument called the galvanome-
ter. which has been made more or less
familiar to many of us by the researches
and lectures of Mr.. Tyndall, was made
use of by Mr. Higgins in these investi-
cations. The instrument was fixed by
Mr. Higgins large refractor, so that the
image of a star formed by the eight-inch
obiect-glass might fall upon the surface
of the thermopiIe. 1t will give some
! token of the care required in researches
of this sort TO mention that the appar-
atus had to be left attached TO the tele-
scope for hours, sometimes for days, un-
! ill the needle whose motion marks the
action of heat had come to perfect rest.
When the time came for making an OBJ
/ servation, the shutter of the dome which
| covers the telescope was opened, and the
telescope was turned upon part OF the
sky near to some bright star, but not actu-
ally under the star. Then the needle was
: watched TO determine whether the
r change of position had produced any ef-
feet. If in four or five minutes no signs
of change were shown, the telescope was
moved over the small distance necessary
to bring the image of the star directly
on the face of the pole. Almost always
the needle began to move as soon as the
; image of the star fell upon il. The tele-
scope was then moved slightly away
again from the star; the needle was then
seen to return to its place. In this way
from ten to twenty observations would
be made upon the same star, so that nc
doubt might remain as to the motion ol
the needle being really due to the stars
heat. In this way il was found
that the bright Arcturus moved the
needle three degrees in about quarter
of an hour. So did Regulus, the leading
brilliant of Leo, the constellation al
present adorned by the splendor of ruddy
Mars. Follux gave a DETECTION of one
and a half degrees; but, singularly
enough, his twin brother Castor pro
= duced no effect at all upon the needle
, The splendid Sirius gave detection o
only two degrees; but, as this star il
always low down, and so shines through
= greater portion of the denser atmos
e pheric strata, it is not surprising that it
= heat should not be prOportioned to it
brilliancy.-LOndOn Daily NctCS.