Lovely name, Della Torre, but how come someone with an Italian sounding name was in London making telescopes in the early 1800s? Anthony Della Torre was working as an Optician in London from 1805 to 1823: he was sometimes known as ‘de la Torre’. He was located at 12 Leigh Street, in Red Lion Square, from 1805-11, and 4 Leigh Street, Red Lion Square, from 1815-23. There’s not a lot known, indeed Leigh Street has disappeared, but if the houses were actually the ones now on Red Lion Square, they were expensive addresses. However not quite in the Strand/High Holborn normal area for telescope makers and traders.
Italian immigrants to London over the last thousand years are discussed on www.italophiles.com, which points out that they were concentrated in the early 1800s in this northern part of London. Amongst their number were various instrument makers – such as Negretti, eventually founding Negretti and Zambra; and Martinelli, who made barometers. There are still many people of this name in the UK, and the USA.
So the telescope dates from the very first 20 years of the 1800s: it is engraved on the first draw, “Della Torre & Co, London”. It is an elegant, narrow bodied, two draw telescope, with a mahogany barrel and lens protectors at each end. The screws that are present mostly look original: one on the objective carrier does look like a replacement. The telescope gives a nice image with an easy focus.
The objective is again a triple lens combination, but compared to the Lincoln this time the Crown glass convex lenses that sandwich the flint glass concave lens (the central lens on the pic with the slight pinkish tint) are very clear of colour, with only the slightest green tint. All are held in place with a screw in ring, much easier to deal with than a peened structure. The objective is small in diameter, with only 18mm of visible glass, within the total telescope OD of 37mm: this is reminiscent of much older Italian (and Dollond C18th) designs. The lens carrier incorporates a sideways sliding cover to protect the objective. As you see, all the screw-threads work well.
Overall length is 49cm (19.4″) extended, and 21.4cm (8.4″) when closed. The eyepiece lenses are in two standard cartridges, but the final connection to the viewing eyepiece cap is novel, in that the shoulder is not part of the cap, it is attached to the first draw permanently.
Altogether a pleasing 200 year old telescope. It was acquisition #167 in 2012. Value now? Difficult to say, as there are very few about, and I’ve never seen another for sale. After listing this here, and receiving some enquiries, I have decided it should be sold, and the price listed on Fleaglass.com is £300.