A late 19th century Rapid symmetrical 8 ½ x 6 ½ camera lens by Ross of London. circa 1875 - 1880.
Serial number: 42602.
Engraved by retailer: Sold by Watson & Sons, 313 High Holborn, London.
Diameter: 7 cm.
Length: 8 cm.
For a similar lens see: The collection of the Science Museum, London. Object No:1979-559/1193