Hi David,
The large lens (7 inch) may well be the original 7 inch f/7 Zeiss astrograph lens that was missing from the Mond when Glyn Marsh and I rescued the instrument from NLO. The 7 inch lens was missing and was not amongst the other astrographic lenses we collected and are now back at NLO with the Cooke/Mond Astrographis mount. The 7 inch that you now have was one that Harold Ridley passed on to Glyn and did not come originally from the NLO.The lens design of the lens you ahve just found may be that of Petzval Doublet. The small 3 inch refractor looks like a guide telescope with a sliding plate that carries the eyepeice and diagaonal across the FOV to allow the observer to selected a guide star. I would guess that both instrument s were part of the original Mond Astrograph or from another of the large telescopes there at NLO. I have taken the liberty of posting your message and images on the Antique Telescope Forum to see if anyone ther can more positivley identify these instruments. Denis Buczynski