Description

Offered for sale is a collectable antique monocular microscope by US manufacturers Spencer Optical Co., which dates to 1917.  There’s a Spencer serial number 44635 on the front of the main tube and a second serial number RD53904 stamped onto the upper limb.  There’s also a plaque on the foot with details of the London retailer and distributor which at the time was H F Angus & Co of Wigmore Street.  The majority of the instrument appears to be in original condition – it has been both well used and looked after by its former custodians.

This example has brass-work such as thumb-wheels which are showing natural signs of age and use-related tarnishing and spotting – the instrument has in general cleaned up reasonably well, with just the right patina for an example from this period and usage profile.

Turning to the technical details.  For the optics, this instrument is fitted with a graduated brass eyepiece draw-tube.  The main tube is also in brass with coarse focus via rack and pinion with a nice smooth action, with the main tube holding in position as it should on adjustment.  Fine focus is a vertical vernier screw/lever arrangement acting against sprung resistance which also works well with just the right amount of resistance to the touch. 

The instrument is supplied with appropriate vintage 7.5x and 10x magnification eyepieces and it’s also supplied with two vintage objectives by Spencer at 10x and 44x magnification, giving a magnification range from 75x to 440x.  I’ve also now added a Watson Versalic 1/12th inch 100x which needs to be used with oil immersion, giving additional options of 750x and 1,000 magnification.

The instrument tilts for inclined viewing, holding in position on inclination as it should and can be tightened further as required.   The stage is a standard ebonite example with a Spencer mechanical over-stage fitted.  This has above-stage x/y controls and adjustable slide clips. The y-axis is a little stiff in operation but functional nonetheless.

The sub-stage has an after-market Abbe-type condenser fitted to the original Spencer condenser mount.  There’s a working iris and also a slot for adding filters.  The condenser mount also has some height adjustment via a helical screw mechanism and also swings out to allow for maintenance or swapping over of the condenser hardware.

There’s also an original Spencer case with the instrument in good condition with internal racking, carry-handle and lock with key present.

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