This small drum microscope is signed on the limb R. Wasserlein, Berlin. As shown in the photos, it measure 10-inches in height when the draw-tube is fulling extended and about 7.5-inches when it is closed. The coarse focusing is by sliding tube and the fine focus works by tilting the stage using a knob that is located under the stage. Below the stage is an aperture wheel. The adjustable mirror is concave. It came supplied with one eyepiece and a divisible objective. This example was found without its storage case. In the 1873 Wasserlein price list (taken from: Das Mikroskop und die mikroskopische Technik, 1873), a drum microscope like the one on this page is described as follows:

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A translation is given below :

"b.   Microscope with drum base; fine adjustment at the stage; Mirror just below the object; 1 Ocular, system 7. Tube with extension to reduce the enlargements to half. With the tube extended, three magnifications from 90 to 300 linear. Instructions for use. In a lockable mahogany case ... 30 Reichsmarks"

The above engraving of the Wasserlein drum microscope was taken from: Das Mikroskop im Dienste des landwirthschaftlichen und gewerblichen Lebens sowie der Familie, 1874.

Louis Bénèche took over the business founded by his father in 1820. In 1850, he brought in Rudolf Wasserlein as a partner. Instruments were signed Bénèche & Wasserlein, Berlin. The firm produced microscopes in the continental style including drum types. Around 1860, the partnership ended and Wasserlein began the manufacture of instruments under his own name. The microscope shown on this page was one of the smallest models in his inventory.