A levelling device, A. Frerk & Sohn, Hanover, late 19th century Brass, steel, glass. Pivoting telescope with tubular level and bubble level, the maker's engraving on the side of the telescope, finely adjustable focuser. Signs of use, optics cloudy. Length of the telescope 33 cm. A. Frerk & Sohn, court mechanic, working in Hanover and Celle, period of production 1863-90. Condition: II

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