Antique 'Martin-Type' Brass Drum Microscope by Thomas Jones
Item
Description
Antique Large Size, 'Martin-Type' Brass Drum Microscope by Thomas Jones, London, with Mahogany Case. This early 1800's microscope, made of lacquered brass is beautifully marked in flowing script on the black barrel with the maker's name and the address of his shop.
This "Drum" type of simple microscope was developed by Benjamin Martin (1704 - 1782) and is a direct in-line tube which carried the optics (eyepiece objective lens) and which slid within a holder. This was also in line with a stage and a sub-stage mirror. Focusing was controlled by 'drawing' the tube up and down. This step was later improved by adding 'rack and pinion' gearing to move the draw tube. This example has a few holes on one side that must have been for a 'rack and pinion' set up. (however there is no space allowance in this case for that setup to fit). There are 4 objectives, (one has no glass) and three additional 'lenses.' The objectives, eyepiece lens, and 3 additional lenses are nice and clear. The swivel/tilt sub-stage mirror is in good condition with a tiny bit of foxing. The 'flame' Mahogany storage case has a beautiful grained lid that has a padded felt liner (no cracks in the case). The lower 'fitted' section is designed to hold the microscope, lenses and other accessories, and there are open sections for forceps and additional lenses, etc. There is also a lower pull-out drawer for store of slides, etc. The case has nice brass hinges and a working brass lock with cartouche plate. Unfortunately there is no key.