"Max Kohl Electromagnet"
Horseshoe electromagnet that operated with an induction coil from the mechanical and electrotechnical workshops founded in 1876 in Berlin by Max Kohl (1853-1908), an entrepreneur in the field of electrical engineering, optics and the mecanic. Max Kohl Aktiengesellschaft (AG) was a manufacturer of devices and equipment for science, technology and industry, based in Chemnitz. Signature painted in gold letters on the base. Model from a college Handwritten number "B2" written in white on the base. Some traces of wear. 
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