CASE-MOUNTED DRUM MICROSCOPE:

DESCRIPTION

A good example of a higher quality case-mounted drum microscope, with original case. The microscope is signed in script, as is a double-pillar microscope in this collection, 'E. Hartnack, Suc'r De G Oberhauser, Place Dauphine 21 Paris.' It has a wide screw on the bottom which screws into the boss on the top of the case; it cannot stand alone. Coarse focus is by push-pull and fine focus by screw tilting the right side of the stage. There is a three-button objective. The microscope has a draw tube. There is a fixed aperture through the stage. The mirror rotates via a knob on the left side. It stores in the fitted hardwood case with cushioned green velvet on the inside of the top lid. There is a small compartment in the case for accessories or slides (none currently present). The eyepiece must be removed and placed in its compartment in order for the scope to fit in its case.

HISTORY OF HARTNACK MICROSCOPES

This microscope was the one recommended by Golding Bird, as early as 1844, as an example of an inexpensive compound microscope that could be satisfactorily used for urinalysis. Originally an Oberhauser product, its production was continued for many years by Edmund Hartnack.

The microscope was made by Edmund Hartnack, who, as the signature says, was the successor to Georges Oberhauser. Hartnack was married to Oberhauser's niece. Oberhauser and Hartnack 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 cataloges are simply lists and not illustrated. The invention of the drum microscope has been attributed to the Englishman Benjamin Martin. Compared to other designs it was very inexpensive to construct. It was produced with many different variations and varied also in quality and usability. Although not the best design, its low cost made it popular and they were produced in France even into the second quarter of the twentieth century. Sears catalogs from the 1930's still show drum microscopes, although by then only smaller and lighter examples were sold, and mainly for amateurs, students, and children. Drum microscopes of the higher quality shown here were long gone by that time.