The daily telegram. [volume] (Clarksburg, W. Va.) 1901-1926, 1914-11-24

/ When this surface is exposed to heat.
the two wires Will generate an cleo
trical current upon exactly the same
principle as an ordinary electrical
battery. The distinctive thing about
this battery is its extreme delicacy
which makes It hard for the average
beholder TO believe that 1t is the work
OF human hands. 1t is this delicacy
which makes It sensitive to the very
slightest changes in Temperature.
This tiny battery Is called Their
mo-couple. 1t is placed in glass
cell, having a fiuoride window,
through which light will pass with
out change or DETECTION A practic-
ally perfect vacuum is maintained in:
1.-THE cell by means Of tube connect
ed with it, and filed with metallic
calcium. which has the property OF
absorbing all of the constituents or
the air except argon.
! This glass cell, containing the
thermo-couple, is placed In the mouth
OF an ordinay astronomical tele-
scope, where the great reflector of
that instrument will focus the light
OF the star to be observed upon the
fuoride window of the cell, and so
upon the absorbent surface Of the
thermo-couple itself. The wires of
the thermo-couple are connected with
a tangent galvanometer, which is an
instrument for measuring electric
current, and thus the heat of any
star is measured In the amount of
electrical current it will generate in
the tiny battery.
Having constructed thermo-
couple Of sufficient delicacy to re-
spond to the heat of stars, the second
difficulty that Mr.. Cobietze faced
was to make a galvanometer delicate
enough to record that current. In the
first place, the galvanometer had to
be protected from the magnetic cur
rents of the earth, and Of all other
magnetic bodies. This 1ss. been ac-
icomphshed in former attempts at the
construction Of such apparatus b,
placing the galvanometer in the CEN
ter OF q great safe OF soft iron, too
soft to retain magnetism. Mr.. Cob
leutze improved upon this by enclos-
ing his instrument In solid, close
fitting coat OF Swedish iron, which Is
very soft, and thus achieved the same
result in much more compact and
manageable form.
Within the galvanometer is the
most delicate part of the whole ap-
Iparatus. It consists in mirror about
the size OF pin head suspended up
on thread OF spun quartz. Mr.. Cob
lentze has large supply OF these
threads Of spun quartz in box lined
with black cloth, but when he shows
them to you, at first you see only the
box. The threads are almost invis-
ible to the naked eye. But IL you look
very closely, you will see that the
box Is filled with IN almost impalp.
able webbing.
Assuming now that the tiny ther-
mo-couple, or battery, is placed in the
mouth Of a telescope, and that the
light Of a star is focused upon 1t, and
that the wires of the tiny battery are
connected with the galvanometer:
The heat Of the star will generate a
current in the thermo-couple, and,
this will be registered in the galyan-
ometer by a slight twisting of the
Quartz thread, and consequently by a
rotation Of the mirror.
| In order to measure the rotation
OF this mirror, an ordinary scale, like
child's ruler, except that 1t is mark
ed OH into millimeters instead OF in
ches, is placed at distance In front
OF the mirror, with q strong light
upon 1t. In the mirror is reflected al
tiny image Of the scale, and upon one
side Of the mirror is still more tiny
mark. The mirror is then observed
through a powerful microscope, and
the slightest detection is measured by
the movement Of this mark along the
Image Of the scale.
Z. When he had completed his instru-
ment last summer, Mr.. Coblentze took
1t out to California and placed it in
the telescope at the famous Lick OBJ
servatory OF Mount Hamilton He made
accurate, cumulative measurements
OF the heat OF 112 celestial bodies:
including los stars; and they were
the first extensive series of such
measurements ever taken. AS an
example OF how much heat reaches
the earth from the stars, Mr.. Coblen-
TIE found that the heat OF Polaris
lthe North starr falling upon a sur
face of one square millimeter, IL. alb
sorbed and conserved continuously,
would require a period OF 100000
years to raise the temperate of one
!, gram OF water on degree centigrade.
He estimated that If the heat of all
, the known stars were concentrated
J upon the same work, 1t would take
them between one and two centuries
to accomplish it Tho rays of the
sun will do it in one minute.
The Yukon territorial council re-
]. Gently passed an ordinance regulat-
Inc. 4la1. HAL.