DESCRIPTION:

The microscope is supported via twin pillars which allow it to incline, the inclination joint attached to the stage on each side. Knurled nuts on each side can adjust the tension on the inclination joint. A pillar extends through the stage to become the tailpiece of thinner diameter. There is no fine focus control. There is a rack and pinion coarse focus only. The slide holder is lyre-shaped and slides down the pillar to hold the slide. There is a substage wheel of apertures. The gimbled mirror is supported by a single thin rod which slides into the substage portion of the pillar. Like most French designs of the nineteenth century, the axle of the focusing pinion is also a thin rod.

HISTORY OF HARTNACK MICROSCOPES

A fairly common design, but with an uncommon signature as most examples of this model were unsigned, although in the author's opinion, likely all were made by Hartnack. There are a few other examples known with various signatures, but none of these are well-documented makers, and in all likelihood were retailers. Hartnack likely sold most of these without his signature, so that the retailers could have their own names inscribed; this was a common practice in the nineteenth century. As the signature says, Edmund Hartnack was the successor to Georges Oberhauser. Hartnack was Oberhauser's nephew and they went into partnership in 1857, Hartnack taking over in 1860, remaining in Paris until 1870. Prazmowski took charge in Paris after 1870, forming Hartnack and Prazmowski, when Hartnack moved to Potsdam, Germany. As with many French makers, Hartnack's early catalogues are simply lists and not illustrated. More than one size of this double pillar microscope were made and slight variations in construction are known.