https://nyheritage.org/collections/pouring-200-inch-disk-corning-glass-works

Skip to main content
Home

Main navigation

  * Collections
  * Organizations
  * Exhibits
  * About

 1. Home
 2. Collections

Pouring the 200 inch disk at Corning Glass Works

Collection Owner:

Corning Museum of Glass - Juliette K. and Leonard S. Rakow Research
Library

Cover Image:
Pouring the 200 inch disk at Corning Glass Works
Ladle used during pouring of 200 inch disk, 1934 - Image Source

Collection Facts

Extent:
20
Dates of Original:
c. 1934 - 1937

Explore the Collection >>>

[                    ]
Go

Historical Context

In 1928, the famed astronomer, George Ellery Hale, had a vision. He
wanted to build the world's largest telescope at Palomar Mountain in
California--a research instrument that would allow scientists to view
the skies as never before. The creation of the largest single piece
of glass ever made was entrusted by Hale in 1929 to Corning Glass
Works using their signature Pyrex(r), a special glass designed to
resist heat expansion. George V. McCauley, a Corning physicist and
engineer, set about achieving what engineers at other companies had
failed to do: casting a 200-inch mirror blank. In March 1934, Corning
poured a 200-inch disk, but part of the mold broke loose during the
pouring, ruining the blank. McCauley decided to continue with
annealing (a process required to slowly cool the glass) as an
experiment. That imperfect disk has become an iconic object in the
collection of The Corning Museum of Glass. It has been suspended in
the same spot for 60 years, since the Museum opened to the public in
1951. The second attempt at pouring was successful, and after a
year's annealing time, the disk was finished and taken by train to
California. The disk was finally installed in 1948 in the Palomar
Observatory, where it remained the world's largest effective
telescope until 1993, aiding in the discovery of quasars and the
first known brown dwarf star. The telescope is still in use.

Scope of Collection

A small collection of photographs and blueprint diagrams which
document the casting and annealing processes for the 200 inch disk.

---------------------------------------------------------------------

Browse within this collection

By Subject:
Glass manufacture New York (State) Corning 20th century
Hale telescope New York 20th century
Palomar Observatory
Optical instruments Design and construction 20th century
Corning Glass Works
Creator Attribution:
Corning Glass Works
Unknown
Ayres A. Stevens, Corning Glass Works
Robert Yarnall Richie, Corning Glass Works

Additional Information

Scope and Content Source:

Browse similar collections

Collection Type:
Photographs

Artistic Works


More Information

  * For Contributors
  * For Educators
  * Citation Information
  * Copyright Statement
  * Contact Us

Empire State Library Network Logo