Offered for sale is a rare variant of the Edinburgh model microscope by W. Watson & Sons Limited of London.  It’s a specialist model, being the No.2 Metallurgical variant of Watson’s popular Edinburgh H model, designed specifically for incident light microscopy and the study of surface features on solid/opaque specimens such as metallic surfaces.  This example dates to around 1936 based on the sequential Watson production number of 59227 which is engraved onto the rear tripod leg.  It appears to be in original condition as far as I can tell and has obviously been well used during its service life.

 

 

In terms of condition the brass-work is showing signs of age and some use-related tarnishing and lacquer losses here and there although not that bad for a well used instrument and it still catches the light quite well. 

The objectives have to be fitted to the optical tube one by one and overall, the range of magnification provided by this metallurgical Watson therefore runs from about 200x to around 1,000x. 

 

There’s a vertical illuminator by C. Baker fitted.  This contains the following:

 

– field iris
– slider adjustment
– second iris
– 6V illumination bulb (working when tested) powered by low voltage Watson supply unit (not supplied as part of listing)
– angled glass reflector

 

The vertical illuminator allows incident/reflected light study of samples – when correctly adjusted it sends a pencil beam of light that hits the glass reflector and is channeled down through the objective lens and onto the subject under examination.  Light is then reflected off the subject back up through objective and into the eyepiece for examination.  At the end of the listing photos you’ll see that the vertical illuminator produces a small spot of yellow/orange light on the sample.  Ideally it needs further adjustment and the glass reflector looks like it needs cleaning or replacing.

 

The instrument tilts for inclined viewing, holding in position as it should and can be tightened at the main pivot as may be required.  The stage is a fully mechanical brass stage as found on the Edinburgh H models, with x/y adjustment controls on the right-hand side of the stage.  It has a pair of stage clips for holding samples steady during viewing and inclination.  The stage has height adjustment via rack and pinion with double-sided thumb-wheel adjustment.  The stage is therefore in theory able to accommodate samples of different thicknesses up to around 3 or 4cm, for inspection via incident illumination.  Stage height adjustment can also be used as the coarse focus control.

 

This being a metallurgical instrument, there’s no technical sub-stage.  There’s also no case with the instrument at present.

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