Delaware gazette and state journal. (Wilmington, Del.) 1883-1902, 1894-06-14
A 5O-INCH TELESCOPE
The Dream of John a. Brashear in il
Fair Way 10 be acknowledgements the
Leading Contributor.

Observatory.
The Dream of John a. lSrnshear in "a
Fair Way 10 be acknowledgements the
Leading Contributor.
A Pit,sburg dispatch to the New
\ ork Sun says; The dream of John y.
Brashcar, pittsburg's famous maker Of
telescope lenses, that Plttsburg and
Allegheny might some day possess tic
largest telescope in the world, is appar-
cnt.y in Ii fair way TO be realized. l'ruf,
kceler, director OF the Allegheny OBJ
seryatory, has also hoped that this might
be accomplished, SO us to afford local
astronomers better facilities To pursue
original Investigation, and establish 4
name for western Pennsylvania in IN
astronomical line. Andrew Carnegie
aua Henry Phipps, Jr., ii is announced
on reliable authority, have oitcrcA y
Contribute the greater part OF the
100000 which will, ut the lowest esti-
mate, be required to equip tic proposed
observatory with the largest lens in the
world. MIR. Carnegie, it is understood,
stands ready 70 pay his subscription Us
soon as the details of cost and cOnstruc-
ton and maintenance can be estimated.
To establish the observatory would
require an outlay Of perhaps 100000,
as it is proposed 10 make lens nifty
inches in diameter. Mr.. BrashGar Is
| confident he can make lens Vi that
| size, but to grind the monster pieces Of
| crown and flint glass, which fit together
to make an aChromatlc rcfracting lens,
would take at least Il year. Then time
I would be needed to get the glass, Is 1t
must be imported from France. The
material must be free from flaws, and in
/ preparing il many valuable pieces
would probably be spoiled. An idea OF
the cost may be imagined when 1t is
known that glass less than foot in
diameter costs $4,000. unmounted.
The tube for the telescope must be at
least 63 feet long, requiring u don't
more than 80 feet III diameter. HE
largest telescope now in use, that at the
Lick Observatory, Mount Hamilton
contains an object glass, 36 inches il
diameter, but two others are now ue!n!
made which outstup II. One is "a
inch glass for Lowe Observatory q
Mount Lowe in Southern California
The other is being ground by AlvaI
Clark's Sons for the Arrkes Observatory
Of the Chicago University, and vii
measure AZ inches. Mr.. lirashear woulI
have constructed this huge lens, but tn
university people were IN Il hurry unt
could not wait for him 10 procure til
glass, and Alvan Clark's Sons secure
the order, as they happened TO have
big glass ON hand.
A few years ago it was considrro,
impossible to make such large tense:
but Mr.. Brashear thinks the limit ha
! I..s.,
! 50.inch lens will mean infinite care, fl
the slightest error will not only pruduc
, u defective glass, but also waste thou
sands OF dollars and months Of valulbl
: time. Mr.. Brashear's friends say theI
! is no doubt that he can perform the LEI
and point to his present work as ey
: dence OF his ability. His most ditiicu
! production is the grating" which
used in spectroseopic work. 1t consis
c OF strip of glass, Oh which are lines
! line that 10000 are drawn in the spaC
c Of one inch. The machinery for doin
y the work is kept in vault Is feet undt
!. ground, and when in motion 10 ell
/ ploye or other person dare approach,
II the heat of the body even several te
distant will affect il. --.
The location OF the telescope is TO
# the mound recently purchased by u
n city Of Allegheny adjacent 10 WatsC
n Park, and which may bear the name
Riverview. Mr.. Brashcar ana P.,
q Keller, tog ether with Mayor KenneS
!. OF Allegheny and James Hunter, VII
/. they Surveyed the site found the loo
i. ton admirable, indeed the best in Ii
,s section Of country.
q The mount contains about 16 acr,
IL and commands view unrestricted
hills or smoke. From the SUNNI
to Sewickley, 10 miles distant, can be see
Mayor Kennedy is in sympathy W
the movement and will lend all the {
in his power. The land belongs TO I
=. city OF Allegheny, and all that will
or necessary is an ordinance from the c
Council deyoting the mount to the p,
id pose.