New-York tribune., 1904-09-04
HARTARD'S NEW TELESCOPE.

The acquisition Of a large rejecting telescope
by the observatory of Harvard University Is
an event of much interest to astronomers
The instrument was formerly the property OF
n noted English amateur, DR.. A. A. Common,
and has already done good work. Shortly
after the death Of the original owner, Harvard
received an anonymous gift OF $4,000, when
made the purchase of the telescope possible.
The bargain has now been consummated and
the apparatus is being packed for shipment 20
this country
Rehectors have certain drawbacks. and are
rarely used except for Photographic purposes
When they have a diameter of three feet or
more however they are apparently superior 10
refractors for such service. An instrument of
the former class, once belonging to DR.. Com
mon and afterward sold to a Mr. Crossley,
was presented to the Lick Observatory five or
six years ago. Much trouble was experienced
mt first in mounting 1t so to follow celes-
tial object satisfactorily, but at last it yielded
astonishing revelations, both Of its own capac-
fly and Of the mysteries Of the heavens. In
the hands of the late James Il. Kecler 1t
showed that nebula are far more abundant
than ANYBODY imagined. Previously they had
been reckoned by the score. or. at the most
by the hundred Professor Keeler calculated
from the number discovered in a small area
by photography, that the visible universe could
not contain less than 120000i Fresh hints
were received, too, concerning the forms of
many nebula and the intimate association of
stars herewith
Harvard already has four or five other tee
scopes, which are used only for photography
One. a refractor, hag a diameter of two feet
and a length of twelve. 1t is now in use at
the station in the Andes. Another also a re-
tractor, was designed for a different kind of
fo hon, hrrv,, oil
times as great as its aperture With this
glass details of lunar scenery have been OBJ
tanned which suggest the possibility of sub
dued volcanic activity ON the moon. Harvard
also has two refectors, each having a d-
ameter Of tWenty-four inches. One of them is
in service at Cambridge and the other in South
America. 1t is the intention of the director of
the Harvard Observatory to retain the Common
telescope at the former place. The atmos-
pheric conditions in the vicinity OF Boston are
not equal to those in the tropics or at a great
elevation in this country 1t is impossible
therefore, to estimate in advance how the ser
vice of the fiye-foot reflector will compare
with that of the Crossley reflector, of which
the aperture is only three feet. If the two were
placed at the same elevation and enjoyed the
same environment the difference in their per-
forTnance should be in proportion to the square
of their respective diameters, or about twenty
FIVE TO nine. The advantage Of greater size
though, will be partially or fully Offset by the
disadvantages of lower altitude and the impure
air always found in the neighborhood of big
cities. The Lick Observatory is exceptionally
fortunate In two respects. 1t stands nearly
mile higher than the Harvard Observatory and
is thoroughly isolated from civilization.
The class of work to which the Common re-
aector will be primarily devoted at Cambridge
is providing means FOR rating the brightness
OF exceedingly faint stars To the measurement
of the 'magnitudes" of the brighter stars Har-
ward has already given much time and labor
1t will soon be in position greatly to extend
the field of inquiry. Much of the earlier COM
putation was done usually, whereas that now