Sir Howard Grubb and the Periscope. Although the principles of the periscope were well known beforehand, Sir Howard Grubb(right) (1844-1931) was the first to design a practical periscope for use in a wartime submarine during WW1. He had worked with his father's firm, the Grubb Telescope Company, which helped to build the Leviathan, mentioned at no. 3 above. Grubb telescopes were also supplied to the Dunsink and Armagh observatories. There is a plaque on his house at Longford Terrace, Monkstown. By the date of the 1911 census he was living in no 14 Orwell Road, Rathgar, and his census return can be seen here.