Description

Offered for sale we have a lovely vintage original Bactil model research-grade monocular microscope by W. Watson & Sons Limited of London.  This particular example dates to 1947 based on the sequential Watson production number of 86833 which is engraved onto the main tube.  It’s in all-original condition as far as I can tell, although the objective lenses may have been changed over at some point in time and this is exactly what you’d expect to see with a working instrument that’s been well maintained.  In general it has obviously been very well looked after by its former custodians, which is nice to see and in this condition it’s capable of giving many more years of service.  It will make a great instrument for those new to microscopy and vintage Watson instruments, as well as also being a good candidate for a seasoned collector seeking a fine example of this era of post-war Watson production.

The Bactil model was one of the largest models in Watson’s range of microscope offerings in this period and a highly capable instrument that often found it way into government and educational establishments in view of its robustness and high quality. This example appears to be no exception to that general rule, with markings on some of the optics for Aberdeen University, with W. W. Scott Ltd of Glasgow the original retailer, with their name on the inside of the case door.

This particular instrument has got very good bright-work details such as thumb-wheels which are showing hardly any age and use-related signs of wear and have polished up very well.  The Bactil is essentially an excellent piece of British optical engineering from this period that oozes the famous Watson brand from its various components, based on quality materials, very solid heavyweight construction and great design.  

The construction is a heavy iron foot with pivot supporting the Lister-type limb also in iron.  Coarse focus is rack and pinion with good smooth action and fine focus is a horizontal arrangement with vernier screw and lever/cam which also works well and the latter has also been cleaned and lubricated.  The stage and sub-stage accessories are all attached to the limb/limb tailpiece and overall this is a very stable well-engineered design.

Turning to the optics, this Bactil microscope is fitted with a chromed eyepiece draw-tube with graduation markings inside the main optical tube which is in brass.  It is also supplied with an appropriate quality vintage eyepieces that with good illumination produce excellent images:

– 6x magnification – unbranded 
– 8x magnification – C. Baker 
– 10x magnification – Watson No. 4

It’s got three vintage objectives on a triple turret, which rotates freely with a nice positive feel as the objectives slot into position as follows:

– 10x magnification – 2/3rds para Watson
– 40x magnification – 1/6th para Watson
– 100x magnification – 1/12th utility Watson – required oil immersion

Overall, the range of magnification provided by this Watson therefore runs from about 60x to a respectable 1,000x when using good illumination and oil immersion techniques with the 1/12th inch objective.

The specimen stage is a circular design by Watson that’s fully mechanical, which works well with x/y controls to the right-hand side.  There’s also no y-axis slippage on inclination.  The stage also has twin slide holder arms one being sprung, for holding slides steady which work well along with two small spring-steel clips that even look like they have retained some of the original factory bluing.   

Turning to the sub-stage, we have a Watson Abbe-type condenser in a friction-fit mount that’s height adjustable via a rack and pinion system.  The condenser also has centering, a working iris to control lighting levels and there’s a 35mm swing-out holder allowing coloured, opaque or dark-field filters to be inserted.  Lighting is via a larger plano-concave mirror on an adjustable brass support arm that slots into the underside of the limb tailpiece, with gimbal and very good silvering to both sides.

The various controls and friction surfaces have been lightly cleaned/lubricated and operate smoothly.

This is a great visual and really good working example of Watson’s Bactil model in monocular configuration that’s also in nice original condition giving excellent usability.  It’s essentially in collectable condition and offered at a sensible price point for a good example from this period of Watson production.  There’s the correct period storage case with this example also in good condition, with internal lens rack, sundries drawer, replacement carry handle and a working lock and key.  It’s also interesting to see that a previous custodian has utilised a George V dated 1917 penny as a washer to use along with the transit bolt – first time I’ve seen something as quirky as this!

Owing to the weight of the microscope, it will be partially dismantled, well 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 a chance.