A 19th Century French Brass Compound achromatic Monocular Microscope, by E. Hartnack & A. Prazmowski. Paris, France, Circa 1880 The tube inscribed 'Mon. E. Hart & A. Prazmowski, A. Prazmouski, Suer., Paris', two way objective, shaped stage, standing on a spur shaped brass base, with two eyepieces, in a dovetailed mahogany case. Measurement: H. 31 cm. catalogue Note: The origins of Hartnack & Prazmowski were in the Parisian optical business founded by Georg Oberhaeuser, who popularised Martin’s drum microscope pattern and developed the horseshoe-footed continental stand. Oberhaeuser began his business in c. 1830 (his shop was located at 19 Place Dauphine in 1832). In 1854, he formed a partnership with his assistant Hartnack (who started working with Oberhaeuser in 1847) and retired shortly afterwards in 1854. The business operated as “Oberhaeuser and Hartnack” until 1859, when Hartnack became the sole owner and the firm became simply “Hartnack”. Hartnack left France in 1870, at the outbreak of the Franco-Prussian War, and went to establish a business in Potsdam, near Berlin, known as Hartnack. The Paris business continued as “Hartnack et Cie” and, later, in 1873, Hartnack and Prazmowski (moving to 1 Rue Bonaparte). Prazmowski took sole ownership of the Paris business in 1878, and later, in 1883, passed it on to his employees Bézu and Hausser. The firm became “Bézu, Hausser et Cie”, although they continued to use Prazmowski’s name until his death in 1885. They sold the business to Alfred Nachet in 1896. Hartnack’s Potsdam business continued after his death until well into the 1900s. Microscope 167 was made by Hartnack & Prazmowski, was known as stand III (Figure 1), and can be dated to c. 1880. The draw tube of the microscope is engraved with ‘Mon E. Hart. & A. Praz., A. Prazmowski sucr, Rue Bonaparte 1, Paris’. There is no indication of serial number in the instrument. Estimate: 200-400