Description

Offered for sale is a good example of an antique monocular brass microscope by Manchester makers J. Casartelli, with the instrument likely to date to the 1865 to 1870 period.  The condition is generally good, with only a few minor age and use appropriate signs of wear to the finish on the instrument and just the right time worn look to its lacquered finish and brass-work.  This example will be quite rare and may well therefore be quite a sought-after example in view of the maker and connection with Manchester.  Being a compact instrument it’s also a good proposition for display, say on a desk-top when set up with a suitable antique slide.  It’s also perfectly usable producing some nice bright images at medium magnification with its current set of optics.

Background to Casartelli, Manchester, England – source Microscope Museum

Guiseppe Luigi Casartelli (1823 – 1900) emigrated as a child from Italy to Liverpool, England, joining a relative’s scientific instrument firm business. He changed his name to Joseph Louis Casartelli and later moved to Manchester where he established himself as a manufacturer of optical equipment, trading at 43 Market Street for many years. Around 1850, Casartelli produced microscopes, telescopes and other optical devices. By the 1870s-80s, Casartelli’s business had evolved and focused on supplying the heavy industries of Manchester, including fittings for steam engines, mining equipment and optical instruments for the fabric industry. One of Casartelli’s sons, Joseph Henry, was made a partner of the company and the business became “J. Casartelli and Son” in 1896. Casartelli’s business moved to 18 Brown Street, Manchester in 1922, acquired the business of another family member in Liverpool in 1929, but was liquidated during the Great Depression in 1933. Parts of the business continued under different ownerships, including the Liverpool business as ‘J. Casartelli & Son (Liverpool)’ (later ‘Casartelli Instruments Ltd.’, in 1984, which closed in 1989), and the original business became ‘J. Casartelli & Son Ltd.’ (and then ‘John Casartelli (M/c) Ltd.’ in 1939).

Turning to the main technical details of this Victorian monocular microscope, we have the following:

1)  Y-shaped foot construction and twin uprights in lacquered brass finish, with Lister-style column/upper limb also in lacquered brass finish.  The instrument is inclinable and holds position well on adjustment.

2)  A monocular eyepiece unit with a top-hat eyepiece giving around 6x magnification.

3)  The instrument’s main coarse focus is controlled by a set of thumb-wheels on the upper limb with smooth action.  The optical tube moves within an outer friction tube and the coarse focus has a straight cut rack – travel and focus are both very good with the optical tube holding in position as it should throughout its working range.  Fine focus is via a single brass thumb-wheel at the front of the optical tube acting on the nose-piece only that also has a smooth action being freshly lubricated.

4)  There’s a single brass objective lens which is unmarked but will be about 1/4 inch giving 25x magnification, currently set to covered – for specimens with cover-slip.

The objective lens and eyepiece supplied therefore provide an effective magnification of around 150x and it’s pleasing to note the RMS fitment, so plenty of other objectives will also fit the instrument. 

5)  The stage is of a square design in brass with some signs of surface patination to the top-plate.  There’s mechanical adjustment for both x and y-axes, with smooth movement from the straight-cut rack & pinion and screw mechanisms.  It’s currently fitted with a ledge for holding slides which works well and a couple of sockets for stage clips or stage tools.

6)  Sub-stage there’s a wheel-of-stops with nicely damped rotation and 4 aperture sizes available.

7)  Lighting is provided by plano-concave mirror on a gimbal mount with height & swing adjustment and silvering showing some age-related foxing/losses to both sides, with reflectivity that’s perfectly adequate.

8)  There is a hardwood base plate attached to the foot giving additional stability and allowing use or display on a polished surface as required.   

In summary, this is a nice clean example of a compact antique monocular microscope from the Victorian period that’s in very good condition for its age from an interesting Manchester maker.  This example may therefore appeal to collectors as well as specialists seeking a quality brass instrument for use and/or display and being compact it’s also a perfect desk-top accessory, especially when set up with an appropriate antique slide – it’s about 14 inches in height when inclined as shown in listing photos.  Also shown set up on a mantelpiece as a display item at the end of the listing photo stream.

For shipping, the instrument will be very well packed and dispatched by insured courier upon receipt of cleared funds.  Overseas buyers please use eBay Global Shipping if it’s available in your territory or contact seller for alternative shipping options/costs.

Thanks for looking.