The evening times., 1911-08-09

ten per cent at time just before
there occurred general fall Of sew
eral degrees from the normal temp
erature of the United States and
Europe. This led to the suspicion
that the term "solar constant" was a
misnomer and that the suns emission
fluctuates. After further studies
along this line in Washington, him
dered by long periods Of cloudiness,
DR.. Abbott was sent by Professor
Langley in 1906 to occupy for the
summer a temporary station on
then has been kept up every year,
with the exception of 1907. when It
was necessary for DR.. Abbot to re-
main In Washington.
In 1909 the measurements which
were being made in Washington and
at Mount Wilson we're supplemented
by similar simultaneous observations
made on Mount Whitney; but as the
weather conditions were not favora-
Bile. Dr. Abbot went again to this sta
ton in 1910.
my expedition" says Dr. Abbot, in
describing the difficulties encounter
ed in getting his valuable instru-
ments up the mountain, which is
nearly three miles high, "lacked the
picturesqueness and eclat which dis
tinguished Langley's many years
previously, with its private car, its
guard OF cavalry and a budding as
tronomer of the first rank, the re-
nowned Keeler, as assistant.
But Killed the Mule.
However, rode over the desert
from Mojave to Lone Pine. about one
hundred and fifty miles. In an auto
mobile. trying all the while desper-
ately to keep my pyrheliometer from
being broken, and was consequently
jounced myself once to the roof of
the automobile and barely escaped a
broken nose. My treasured pyrhelio-
meter afterward rolled down the
Mount Whitney trail twice with the
pack mule, and the second time the
mule was killed; but the instrument
reached the top in safety"
Before presenting the matter to
congress Secretary c. D. Walcott OF
the Smithsonian institution wrote to
the leading astronomers Of America
and Europe, asking their opinions.
Without exception they answered that
II the measurements made in south
ern Mexico checked those made at
Mount Wilson simultaneously 1t
would be proof positive of DR.. Alb
bots theory. At the same time these
scientists took occasion to express
their high admiration for the work
which DR.. Abbot is doing, many
speaking of him particularly as q
worthy successor Of the lamented
Langley.
In speaking Of his work and what
he hopes to accomplish DR.. Abbot
says:
"The measurements we have made
show on their face range in the
solar radiation outside Of our atmos.
phere of about eight per cent Nov
the question is: Is this variation
real, or is 1t brought about by inac.
curacies of observation. or by some
error In determining the losses ex.
perienced In the air?
III the measurements were inac.
curate. and the range Of variation
were due to that, we would expect
the measurements of successive day,
to vary irregularly: but as matter
Of fact the successive days Of obser.
walton show Q regular march from
the higher to the lower and bacl
again, showing that 1t is not mere
accidental fiuctuation Of observation
but something either in the air or II
the sun that 10 causing It.
Does the Sun Vary.
"As we have measured simultane
ously 1T the sea-level in Washington
at one mile elevation on Mount VIII.
son and three miles elevation or
Mount Whitney. without . difference
lin the results outside the atmosphere