EMIL BUSCH COMPOUND MICROSCOPE

DESCRIPTION:
This is a highly portable compound microscope with a gloss black and nickel plated finish. The term 'Pocket Microscope' may be a bit of an overstatement, as the box is bulkier than the usual pocket. The microscope supports it optics an a vertical fixed limb which cannot incline but still follows the Lister limb principal in that it is made from one solid piece of metal from tube support to foot, including the stage. The foot is oval and about 2 ⁵/₈ X 2 ³/₈ inches in diameters. Focus is push-pull through the sleeve. There is no fine focus. There is a draw tube with divisions reflecting the possible variations in magnification. A single piece of metal forms a double stage clip and is fastened to the limb itself. The mirror rotates on an axle that passes through to foot; this miror can rotate in one axis only, so the light source must be positioned in front of the microscope. The mirror may be removed so that the foot of the microscope fits over the tube of a projecting light source so that it can serve as a projecting microscope. The objective is divisible into two parts and as the brochure states, the powers from 30 to 75X are obtained with the distal elements removed and the higher powers of 100 through 200 are obtrained with the objective undivided. The draw tube has calibration markings for all these magnifications.

The tan leather covered box is labeled 'Pocket Microscope, Busch'. The box measures about 6 X 3 ³/₈ X 3 inches.The box is lined in dark green velvet. It has a sleeve to hold a single slide. Besides the microscope with its single divisible objective, orthoscopic eyepiece, and the single slide no other items were supplied with the microscope. Two different cases were available, the hard case shown here or a leather pouch with drawstring.

HISTORY: In general, Busch microscopes are not rare as many were produced. They were exported to the USA in the early 20th century and were sold by retailers like P. Aloe. The stands are of reasonably good quality construction. Like the other German microscope makers, they made several different sizes of stand, and two larger stands, a small student stand and a large first class stand are also part of this collection. Emil Busch took over an optics firm from his uncle August Duncker in about 1845 and built a considerable enterprise that grew even after his death in 1888. The firm prospered making photographic equipment, binoculars, etc until WWII. Their pocket microscope was apparently quite popular, and they also made miniature binoculars. Remnants of the company were absorbed by optical companies in East Germany after WWII. Zeiss may have supplied their optical glass.