The Indianapolis journal. [volume] (Indianapolis [Ind.]) 1867-1904, 1894-06-13
MONSTER TELESCOPE
PITTSBURG TO BE THE SITE OF THE
LARGEST IN THE WORLD.
1t VIII BE Si~xty-Three Feet Long,
Mr.. Carnegie and Henry Phipps.

PITTSBURG, June 1.-THE dream Of
John A. Brashear, Pittsburg's famous MAX
er of telescope lenses, that Pittsburg and
Allegheny might some day possess the larg-
est telescope in the world, is apparently in
a fair way to be realized. Professor Keller,
director Of the Allegheny observatory, has
also hoped that this might be accomplished.
so as to afford local astronomers better IA
cilfties to pursue original investigation, and
establish a name for western Pennsylvania
in an astronomical line. Andrew Carnegie
and Henry Phipps, jr., it is announced on
reliable authority, have offered to contrib
ute the greater part of the $4,000 which
will, at the lowest estimate, be required to
equip the proposed observatory with the
largest lens In the world. Mr.. Carnegie, ii
Is understood, stands ready to. pay his sub
scription as soon as the details Of cost
and construction and maintenance can be
estimated.
To establish the conservatory would re-
quire an outlay of perhaps $500, OOO, as it
is proposed to make a lens fifty inches in
diameter. Mr.. Brashear is confident that
he can make a lens of that size, but to
grind the monster pieces of crown and flint
glass, which fit together to make an
achromatic refracting lens, would take at
least a year. Then time would be needed
TO get the glass; as it must be imported
from France, The material must be free
from flaws, and in preparing 1t many val
liable pieces would probably be spoiled. An
is known that a glass less than a foot in
diameter costs $4,000. unmounted.
The tube for the telescope must be at
dome more than fifty feet in diameter.
The largest telescope now in use, that at
the Lick Observatory. Mount Hamilton.
in diameter. but two others are now being
made which, outstrip it; One is a thirty
servatory. on Mount Lowe, in southern
California The other is being ground by
Alvin Clark's sons for the Yerkes Observ-
atory of the Chicago University, and will
measure forty-two inches. Mr.. Brashear
would have constructed this huge lens, but
eoe an mot wait f RepPhlis m were te er lm a h the gla ana
and Alvin Clark's sons secured the order,
as. they happened to have a big glass On
hand.
A few years ago it was considered impos-
sible to make such large lenses, but Mr..
Brashear thinks the limit has by no means
been cached. To grind a fifty-inch lens will
mean infinite care, for the slightest error
will not only produce a defective glass. but
of valuable time. Mr.. Brashear's friends
say there is no doubt that he can perform
the fess and az n|Ps 0i nsll ie his H Hges most w SIFisou af
production is the grating which is used
In spectroscopic work. 1t consists of a
that 10000 are drawn in the space Of one
inch. The machinery for doing the work
is kept In a vault fifteen feet underground,
and when In motion no employee or other
person dare approach, as the heat of the
body even several feet distant will af-
feet 1t.
The location of the telescope is to be the
mound recently purchased by the city of
Allegheny adjacent to. Watson Park. and
which may bear the name of Riverview.
Mr.. Brashear and Professor Keller, togeth-
er with Mayor Kennedy. of Allegheny, and
James Hunter, when they surveyed the site
found the location admirable; indeed, the
best in this section of the country. The
mount contains about sixteen acres, and
commands a view unobstructed by hills or
smoke. From the summit, Sewickley, thir-
teen miles distant, can be seen.