Markree Observatory

thumb| using the refracting telescope at Markree Observatory

Markree Observatory was an astronomical observatory in County Sligo, Ireland. The asteroid 9 Metis was discovered from this observatory in 1848 by Cooper's assistant Andrew Graham using a comet seeker telescope. In the later 1800s it was operated again after a brief hiatus, and gained note for its meteorological observations and research on double stars.

For a number of years Cooper's big refractor was the largest in the world. He used the telescope to sketch Halley's comet in 1835 and to view the solar eclipse of 15 May 1836.

Later a 5-foot (1.5m) transit and a 3-foot (0.9m) meridian circle, fitted with an interchangeable 7-inch (17.75 cm) glass were added, which was the largest at that time in 1839; also in 1842 a 3-inch comet seeker was added.

"The Observatory of Mr Cooper of Markree Castleundoubtedly the most richly furnished private observatory knownis worked with great activity by Mr Cooper himself and by his very able assistant, Mr Andrew Graham." (Royal Astronomical Society, 1851)

In 1848, Cooper's assistant, Andrew Graham, discovered the asteroid 9 Metis with a wide-field comet seeker telescope manufactured by Ertel. Graham resigned his post at Markree in 1860, but continued his research at Cambridge Observatory until his retirement in 1905. E.J. Cooper died in 1863, but the observatory remained active until the death of Edward Henry Cooper MP in 1902.

The 13+ inch Cauchoix

The Cauchoix telescope was installed inside a circular wall, but it had no dome or roof over it.

The Grubb mounting had a clockwork drive and weighed almost 2.4 metric tons (2.6 US tons), which rested on a limestone pillar. The 13.3 inch lens was completed in 1831.) was a Swiss who in the late 1700s came up with a breakthrough for making better quality and larger glass, and in time went on to teach a young Fraunhofer at Joseph von Utzschneider's (1763-1840) glassworks, and eventually started his own optical glass works. Guinand would supply glass for the Paris Observatory telescopes and also Cauchoix.