Evening star., 1925-04-02
EXPEDITION TO STUDY
HEAT OF SUN PROJECTED HERE
Daily Dissertations May
Aid in FOrecdsting
Heather.
Geographic Society and
Smithsonian Viii CO.
Operate in York.


day announced that it will send, in
cooperation with the Smithsonian
Institution, an expedition half way
around the world for a remarkable
purpose-to make daily measure of
the heat of the sun.
To the layman such an inquiry ap-
pears an ultra-refinement of scien-
tific research. but, should the joint
expedition work out the findings it
hopes for from it's studies. all civil
lied mankind will benefit by the re-
suits.
The observations Will extend over
four years. They will be made to
determine a method of long-range
weather forecasting by which it is
hoped a cyclone across our Middle
West, stormes al sea, a week or rain
less days for a county fair, or the
last frost of Spring can be predicted
well in advance.
The expedition will be known as
THE National Geographic Society's
Solar Radiation Expedition, in Co.
operation With the Smithsonian Insti-
tuition, according to the announce
ment of DR.. Gilbert Grosvenor, pres
ident of the society, and its purpose.
as officially defined, Is ito carry on
for four years daily observa tions of
the solar constant of radiation in a
manner suitable to measure the vari-
alton of the SUM-
DIR. Abbot in Charge.
Dr. Charles G. Abbot, director of
the Smithsonian Institutions Astro-
physical Observatory, who has been
called the Isaac Newton of the laws
of the sun, will be the expedition
leader
The work of solar observation has
been carried on by Dr.. Abbot and his
associates at the Smithsonian's astro-
physical observatory since 1902. At
first observations were made for a
part of each year at Mount Wilson,
Calf. In 1918 a station was estab-
Hshed in the nitrate desert of Chile
and two years later a station was set
up on Mount Harqua Hala, in Arizona.
which took over the work previously
done at Mount Wilson The estab-
lishment of the new station will add
to the value of the work of the two
stations already established.
The results of these solar radiation
strides have been acclaimed by the
scientific world. The reason for max
ing them was humorously put by a
member of Congress, who, advocating
more appropriations for the work,
which has been handicapped for lack
of funds. said: We'll, since every
thing comes from the sun, 1 think we
ought to provide money to gate
that, too"
DR.. Abbot will make a preliminary
survey of points in Asia and Africa
before it is decided where to estab-
lish a field station for the proposed
expedition.
Sheds Equal Heat.
The principle underlying the inves-
LEGATIONS is that the sun sheds it's life
heat equally on every square inch of
the outer surface of our planet ex-
posed to it-only the outer surface in
this case is the surface. of the ocean
of air in which we live, and not the
surface of the earth on which we
move.
The solar geographers task would
be easy if men, like fish, could arise
to the surface of their air ocean.
Since man cannot do that he must
devise ways to overcome the inter-
ference of vapors and dust particles
that affect a sunbeam the instant it
strikes the outer rim of our air
envelope.
1t is to discount this interference
that Dr. Abbot has spent decades in
devising unique instruments, which
the expedition will use, and in per-
fecting others which the late Samuel
Pierpont Langley invented. 1t was
recalled today that an early impetus
was given to the study of solar
radiation by a former president of
the National Geographic Society, DR..
Alexander Graham Bell, when, in
1892, he contributed 5000 to the
Astrophysical Observatory of the
Smithsonian Institution to start
studying solar radiation. Today the
National Geographic Society set aside
s55,000 to be expended in the four
years study which may bring the
dream of long range weather fore
casting to a practical realization.
Variations of Weather.
The lay>man usually is astounded
when told that all our weatherthe
rains and the SHOWS, the storms and
the droughts-have their origin in
the slight variation of heat we get
from the sun This variation over
short periods is only 3 or per cent;
in the 20 years of DR.. Abbots study
it's outside limits have only been be-
tween 10 and IL per cent.
The highly complex effects of this
variation in different localities is the
result of the earth's variegated
geography. Air, like humans, is re-
sponsive to the company it keeps, and
a change of heat impaired affects
tains, deserts, oceans and plateaus.
Whereupon the extremely fluid at
mosphere seeks to readjust itself
and the various kinds of weather"
ensue.
In passing it should be noted that
it it not merely temperatures of the
sun rays that are to be taken, but the
heat, which implies energy, SO that
the measure is in terms of calories-
number of "calories per square cent?
meter per minute"
Standard of Measurement.
This means that if you had a cube
of water the size of a dice, and this
water were blackened so 1t would
absorb heat, and if you could carry
1t outside the atmosphere SO the suns
rays could strike 1t head on" those
rays would warm it two degrees per
minute.
The first instrument devised to
take the pulse" of q sunbeam IS a
comparatively simple mechanism with
a long name-the pyrheliometer. A
long tube catches the suns rays and
projects them upon a blackened silver
disk, which is connected with ther-
mometer. Obviously this instrument
registers the sunbeam IF. o. B."-not
as II lelt the sun out dS II TedCHe Is
the observer after it's drive through
the air has distorted it.
To discount this distortion, advan-
tage Is taken of the fact that differ
| ent parts, or wave lengths, of a light
ray are affected in different degrees
by the distractions they meet. An
| instrument of extreme delicacy has
| been devised to assess the intensity
| Of each part OF the spectrum-an in
/ NT.N l.. - n til,
| registers temperature change down
| 10 nnn IN lllLonth OF a degreei