Elizabeth daily monitor. [volume] (Elizabeth, N.J.) 1868-1880, 1869-04-22
Elizabeth Daily aonitor,
AT 155 BROAD STREET, BY
j. MADISON DRAKE.
WARMTH on THE STARS.

by multitude of sparkling orbs, the
idea of heat is not Suggested by their
splendor. 1t will, therefore, seem sur
prising to many that men of science
should assign no uncomfortable por.
ton Of SElr terrestrial heat-supply to
those distant twinkling lamps. 1t is
not many years since Professor Hop.
kins, of Cambridge, went even further,
and expressed his belief that if the
earth's atmosphere were but increased
some $4,000 yards in height, so as to
have an increased power of retaining
the warmth poured upon it from outer
space, we might do without the sun al
together so far as our best supply is
concerned. As a glass-house collects
the suns heat, and renders it available
during the time that the sun is below
the horizon, so he held that the addi-
tional layer of air would serve to gar
ner the warmth of the stars in quanti-
ties sufficient for all our requirements.
But until lately all these views, how
ever plausible they might have seemed,
had not been founded upon facts OBJ
served. Mr. Higgins, the physicist
and astronomer, has just published the
results of series of inquiries addressed
to the actual measurement of heat
which we receive from the leading
brilliants of the nocturnal sky. The
instrument called the galvanometer,
which has been made more or less
familiar to many of us by the research
es and lectures of Mr.. Tyndall, was
made use of by Mr.. Higgins in these
Investigations. We need not consider
the construction of this instrument, or
the manner in which heat acts upon it
through the agency of what is called
the thermo-electric pile; all that is
necessary to be known is the fact that
the qualities of the instrument as
measurer of delicate heat effects are
thoroughly established, so that no
doubt can exist as to the significance
of its indications. The instrument was
fixed to Mr.. Higgins large refractors
so that the image of a star formed by
the S-inch object glass might fall upon
the surface of the thermopile. It will
give some token of the care required in
researches of the sort to mention that
the apparatus had to be left attached
to the telescope for hours, sometimes
for days, until the needle whose mo-
tons mark the action of the heat had
come to perfect rest. When the time
came for making observation, the shut
ter of the dome which covers the teles-
cope was opened, and the telescope
was turned upon part of the sky,
near to some bright star but not ac-
tually upon the star. Then the needle
was watchedsto determine whether the
change of position had produced any
effect. For clearly it is necessary in
case of this sort to see that no cause
except the one to be examined is eX-
ercising any influence. 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 it. The tel
escope was then moved slightly away
from the star the needle was then
seen to return to its place. In this way
from twelve to twenty observations
would be made upon the same star, so
that no doubt might remain as to
the motion of the needle being really
due to the stars heat.
In this way it was found that t e
bright Arcturus moved the needle three
degrees in about a quarter of an
hour. So did Regulus. the leading
brilliant of Leo, the constellation at
present adorned by the splendor of
ruddy Mars. Pollux gave DETECTION
of IL degrees but, singularly enough.
his twin brother Castor produced no
effect at all upon the needle. IL
splendid Sirius gave DETECTION of o "
two degrees ; but as this star is always
low down, and SO shines through a
greater proportion of the denser atmos-
pheric strata, it is not surprising that
its heat should not be proportional to
its brilliancy.
These inquiries are singularly inter-
estine, the more so when we remember
that the full moon, which outshines so
many fold the stellar glories of the
heavens gives us either no warmth
whatever, or so little that no expert
ments have ever certified US that we
receive any from her Mr.. Higgins
has tried the moon with his powerful
aalvanometer. with results which are
not by any means satisfactory or act
cordent, but which are sufficient to show
that we receive scarcely trace of heat
from the pale-faced orb.