Quote Originally Posted by Steven Tribe View Post
I have a teeny weeny problem with 552! Morley apparently engraved his name/address and reference number on both new and secondhand items sold from his establishment......So the Morley address doesn't always show the date of production!
Interesting because I suspect that J Solomon was Grubb's first representative (the 1859 advertisement refers to an earlier (April 9, No 82 of the Photographic Journal which I cannot find - most 'bound copies have had their adverts removed) advert by J Solomon in London) so this makes sense. That said, The Patent for the Aplanatic was filed on 8/10/57 and sealed on 6/4/58 so I'd be dubious of any lens engraved patent being made prior to October '57. The Science Museum hold 647 which they say was from 1857. I'm writing stuff up but my best guess is that most of the 'early' lenses were built between 1857 and 1865 because in 1865 Thomas Grubb took on the manufacture of the Great Melbourene Telescope (worth searching the web for - it was damaged in a severe bush fire and is, I think, being restored but with difficulty due to its exacting construction) which was an enormous undertaking and potentially meant that any lenses sold after this date were from stock.

That said, there are some fascinating vagaries which William and I are discussing.