Grand Model 'van Heurck' microscope with case and accesories, c 1900.
© Science Museum / Science & Society Picture Library
Made by W Watson and Sons of London, this instrument, introduced in 1895, was Watson's largest and most fully fitted research microscope. Large in size, with many refinements including rack and pinion adjustment to the draw tube, wide diameter body tube, slow-acting fine adjustment, double concentric controls to the rotation mechanical stage, and fine as well as coarse focusing adjustment to the sub-stage. The instrument has a wide range of accesories.