Groth's universal apparatus:- vertical polariscope with arrangements for parallel and convergent light, in two boxes, etc. Groth's universal apparatus: vertical polariscope, with two cases, plus components
Plurostat Earthfree Universal apparatus, standard model, providing electrical currents and motor-drive for miscellaneous therapeutic, surgical and diagnostic purposes, Cox-Cavendish, England, 1910-1930 Plurostat Earthfree Universal apparatus 1910-1930