second number on the stage of 40021.
This is an example of the Wild M11 portable microscope. As in the case of Wild theodolites, this instrument fits into a bullet case which stands 15" high. It can be carried by a leather strap which fits over the top and connects to the latches at the bottom. A circular base measuring 6 7/8 inches in diameter also acts as the bottom of the case. A double sided mirror plugs into the center of the base. This instrument features an inclining monocular tube with a 45 degree prism inside a rotating housing. It also features a revolving nosepiece which holds a set of four Wild objectives having magnifications of 4X, 10X, 20x, 40X and 100X, the immersion objective being stored on the accessories tray along with an Immersion Oil bottle. Also present are two Wild eyepieces with magnifications of 10X & 6X. The coarse focus adjustment is by rack & pinion acting on the body tube. Fine focus movement acts on the stage with micrometer screw adjustment. The stage measures 5" by 5", and works by a floating stage movement. Below the stage is an adjustable Abbe condenser having a nA of 1.30 (swing-out type). There is also a very convenient plastic accessory tray which can be slid into place under the stage. This tray holds four objectives and two eyepieces with a tube for an immersion bottle.
The firm of Wild was established in 1921. It began primarily as a maker of surveying instruments. Their first microscope was made in 1939. The Wild M11 was first made in 1954. In 1971 the firm began a co-operate in marketing with Leitz and in 1972 Wild acquired shares of Leitz. A controlling interest was taken by Wild in 1975 and in 1990 Leica plc was formed, including the Wild, Reichert, Leitz, Jung, Cambridge Instruments, and Kern Swiss companies. The group headquarters remained in Heerbrugg.