Mountain Observatories [pp. 33-44]

By permission of McClure's Magazine
ON THE WAY TO THE MONT-BLANC OBSERVATORY (Passage of a Crevasse)
observatory at some point on the Pacific
Railroad at as high an altitude as possible
where the clearness of the atmosphere and
the great number of cloudless days would
ensure unsurpassed opportunities for astronomical observation."
It is noteworthy that the clearness of the
atmosphere was the only point spoken of.
Nothing was said of the steadiness — by
far the most important factor.
Congress granted an appropriation and
expeditions were sent in 1872 under Mr.
Cutts and Professor Davidson to points in
the Rocky mountains and in the Sierra
Nevada. Professor Young accompanied the
former expedition and his remarkable success in solar spectroscopic observation at
his elevated station was soon widely known.
In the years 1872-73 the question of a suitable site for the twenty-six inch refractor
of the United States Naval Observatory
(then building) was frequently discussed
among astronomers.
In the summer of the latter year I made
35
a long stay in the Rocky mountains of Colorado and reported adversely on the suggestion to move the twenty-six-inch telescope
to the region examined. The skies were
:clear, but the stars were most unsteady.
No high magnifying powers could be employed, and no delicate observations made.
The eclipse expeditions of July, 1878, to the
Rocky mountains of Wyoming and Colorado
familiarized many astronomers with the question, and the general verdict on these regions was that the skies were extraordinarily clear, while at the same time the stars
were so unsteady as to preclude refined observations. Professor Langley's famous
expedition to Mount Whitney in Southern
California (1881) showed, on the other hand,
that this particular station combined both
the requisites of a pure and quiet air.
The plans for Mr. Lick's observatory on
Mount Hamilton (4209 feet in height) were
made in 1874, and the observations made
there in 1879,1881, and 1882, called attention to the excellence of the selected site.