In 1871 the foundation of the College of Physical Sciences was founded in Newcastle in 1871, it was renamed the Armstrong College in 1904 after William George Armstrong the engineer and industrialist. I 1908 it would become part of the university of Durham.
A 4.5 inch Thomas Cooke & Sons was presented to Armstrong College in 1915 possibly by a local historian J A Wellford.
The telescope was still in use in the 1960s when land at Close House Mansion, Heddon on the Wall, Northumberland was acquired by Kings College Newcastle, later renamed Newcastle University. This was known as the Espin Observatory.
The Espin Observatory contained telescopes used by the Rev THEC Espin 1858-1934 of Tow Law in County Durham including a 24 inch reflector made by George Calver in 1914.
The Cooke was in use until the early 2000s until the site was sold for re development the Cooke was removed and I don’t know where the location of it is today.