Description

Background to Andrew Ross & Co.

Andrew Ross founded his business in 1830 and, like James Smith, later of Smith & Beck, he collaborated with J.J. Lister, the manufacturing optician who invented a mathematical method of producing high quality objectives. Ross’s early instruments were constructed initially in a fashion similar to other contemporary makers, including a construction style similar to that of the Lister-limb design.  He continued this practice until 1840 when he developed the “bar-limb”, a very stable design and from then on also supported his stands on the classic Y-shaped foot with two upright supports. Andrew Ross died in 1859 and his son Thomas Ross carried on the business. Thomas Ross died about 1870 and the management of the firm was taken over by famous inventor Francis Wenham who was responsible for the development of new models such as the Ross-Zentmayer models in the 1880s and they remained in production into the 1890s until replaced by continental designs such as this example. The Ross company went on to produce optical products well into the twentieth century, although large high-quality microscopes became less important to the firm as the years went by. The firm was called Ross & Co between 1837 and 1841, then Andrew Ross & Co and finally Ross Limited from 1897 onwards. The firm discontinued the production of microscopes in 1906. (Source: Antique Microscopes’ website)

This example of a Ross bar-limb pattern microscope presents well with some lovely gleaming brass-work details and age-appropriate patination here and there, although nothing that significantly dents the visual appeal, which is what you’d hope for with an antique instrument of this age.  The instrument’s look and feel is of a quality not found in modern microscopes in that’s it’s fashioned from solid brass, giving it a really weighty feel.  It’s a mid-sized instrument and despite its modest dimensions, it does command quite a presence with a working height approaching 18 inches.  It also has a hardwood base-plate allowing use or display on a polished surface if so desired.

Technical details – the construction is a brass Y-shaped foot with twin uprights supporting a pivot and a bar-limb arrangement, with square section slider and horizontal cut rack as one would expect with a Ross of this vintage.  The coarse focus has a fairly smooth action with no damaged teeth that I could detect and holds in position as it should in its working range, with some lateral play, which I’ll endeavour to tighten.  Fine focus is not supplied on this instrument. 

In terms of its optics, this microscope has a brass main tube without draw-tube and a single eyepiece of approx. 8x magnification that with correct illumination produces bright age-appropriate images.  It’s also got a single Ross objectives as follows:

– 1 inch – 6x magnification – non-RMS – dated 1856

I’ve tested the optics with various antique slides and the images produced are perfectly acceptable when using good illumination. The magnification available with the instrument with its current set of optics will be around 48x.

The instrument tilts for inclined viewing and holds in position as it should on inclination.  The brass specimen stage is rectangular and non-rotating and it has a rest for slides that moves manually along the y-axis, working well and holding position as it should.

There’s no technical sub-stage fitted and lighting is via a replacement plano-concave mirror in an original Ross gimbal mount with swing, rotation and height adjustment, with decent silvering to both sides. 

The instrument has been very gently dusted and also lightly lubricated with non-hardening grease where appropriate, so that the controls operate smoothly.  This example displays well having some lovely brass-work with mellow golden tones which catch the light beautifully as well as most of its originality, as I hope the listing photos demonstrate.  This antique microscope is very much a usable proposition for low-powered work such as entomology with its current set-up and with the addition of further Ross (non-RMS) objectives, its magnification and capabilities will extend further.  It’s offered at a very good price point for a Ross of this age, type and condition.  As well as its usability, the instrument is also suited as an antique display piece in a library or home office type of setting, especially when set up with an appropriate antique slide.  There’s also no storage case at the present time.

Owing to the weight and delicacy of this antique microscope, it will be partially dismantled, carefully wrapped for shipping and dispatched by insured courier upon receipt of cleared funds. 

Thanks for looking – please also check out my other listings if you get the chance.