'Royal' Binocular/Monocular Microscope with Accessories and Case, by W. Watson & Sons, London, c.1910

Watson & Sons royal binocular/monocular microscope. The limb is carried on trunnions on a tripod of blackened brass with circular feet. A micrometre screw on the limb adjusts the fine focus and the body is mounted on a rack and pinion for coarse focusing. There is a choice of a monocular body with a graduated draw tube or a binocular body. A Zeiss double objective changer screws into the lower end of the body. The stage is mechanical, moved by rack and pinions. Two Vernier scales show the degree of movement in each direction. Specimens are held on the stage plate by two spring clips. The sub stage condenser can be focused, aligned and is fitted with an iris diaphragm. The mount allows it to swing out from beneath the stage. A Plano-concave mirror in a horseshoe set on an arm on the lower end of the limb. The wooden case also holds three Leitz objectives, one Zeiss objective, two eyepieces and a dark-ground condenser. Sir Charles William Oatley (1904-1996) was the inventor of the scanning electron microscope, which he developed in the Department of Engineering at Cambridge between 1945 and about 1960. The instrument became available commercially in 1965. This Watson 'Royal' was acquired by his father, a scientific amateur, about 1910, and Oatley was introduced to microscopy and taught how to use it as a young boy.