Refracting telescope with equatorial mounting, Washington DC, USA, 1876.

Refracting telescope with equatorial mounting, Washington DC, USA, 1876.

Refracting telescope at the Pulkowa Observatory, St Petersburg, Rusia, 1876.

Refracting telescope by M Herbst, St Petersburg, Rusia, 1876.

Refracting telescope, 1870-80.

Equatorial refracting telescope, Paris Observatory, France, 1884.

The great refracting telescope, Vienna, Austria, 1881.

Sectioned refracting telescope, 18th century.

Refracting telescope, Grubb, Parsons & Company, Newcastle upon Tyne, 1931.

Mr Cooper's refracting telescope, 23 September 1831.

Refracting telescope of 3 1/4 inch aperture, 1800-1860.

'R S Newall's Telescope', 1872.