Thomas Grubb started as a cast-iron billiard table manufacturer in Dublin, then turned to designing and manufacturing engraving equipment and printing machinery. Throughout his career his main income came from his position as Engineer to the Bank of Ireland.
Grubb made his first large telescope for Markree Observatory in Ireland in 1834, then a 15 inch reflecting telescope for Amargh Observatory in Ireland and, in 1838, a refractor for Greenwich Observatory.
He was a close friend of Thomas Romney Robinson, director of Armagh Observatory. Grubb and Robinson were actively involved in the proposed design for a large reflecting telescope in the southern hemisphere in the early 1850s. The design for this equatorially mounted reflecting telescope would serve as the basis for Grubb's design for the Great Melbourne Telescope a decade later.
The contract awarded in 1866 to build the Great Melbourne Telescope further established Grubb's career, and he established a new business and workshop in Dublin to cast the speculum mirrors and construct the telescope. Thomas was so busy with his work at the Bank of Ireland that he withdrew his son Howard from university so that he could oversee the construction of the telescope.
When doubts about the design and construction of the telescope surfaced after its erection in Melbourne, Grubb prepared a detailed pamphlet refuting the criticisms. Astronomer Royal George Airy, who had previously seen Grubb as simply a skilled mechanic, was deeply impressed by his mathematical knowledge of optics.
The Great Melbourne Telescope clearly demonstrated Grubb's design and manufacturing skill, and his firm would go on to design and make many more major telescopes, including the Great Vienna Telescope (1878), the world's largest refracting telescope at the time. In 1925 the company became Grubb Parsons and continued to manufacture large telescopes until it ceased in 1985.
Glass, I. S. (1997). Victorian Telescope Makers: The Lives and Letters of Thomas and Howard Grubb, Institute of Physics Publishing, Bristol.
Robinson, T. R. & Grubb, Thomas (1868). 'Description of the Great Melbourne Telescope', Proceedings of the Royal Society of London, 159, pp.127-161.