Allegheny Observatory

Identifiers

Open LibraryOL15227941A

Top Subjects

Clocks and watches (1)
Railroads (1)
Pennsylvania (1)

Books by Allegheny Observatory

Total count: 2

A proposal is herewith submitted to you for regulating, from this Observatory, the clocks of the Pennsylvania Central, and other railroads associated with it

Allegheny Observatory1869-01-01
On the cheapest form of lightfrom studies at the Allegheny observatory

1890-01-01