A fabulous unsigned all brass Carpenter-type monocular microscope with rarely seen options/accessories c.1820. Transition features between a Jones Most Improved and the improvements of Carpenter can be seen as well. The folding/collapsible tripod base is classic Jones/Dollond. The compass joint at the base is an earlier adaptation (Bleuler, Shuttleworth c.1780) and accomodates the 3" plano, one sided mirror.

Coarse focussing using a  knurled knob is by rack and pinion on a triangular limb (again late 18th century styling). The sprung, square stage is attached to this focussing system and can accomodate the hand magnifier (used as a live box) and a B/W  ivory disk. Fine focussing is accomplished by a separate knob near the nose that moves outward as the heavy internal copper spring decompresses (see photo). The action is flawless and accurate. I have never seen this innovation before on such an early microscope!

The upper arm is on a compass-type joint and holds the body tube in place by friction fit. Without using the 150mm. body tube (extending to 200 mm.), this microscope can be used as a simple microscope with the assistance of a high power over-sized objective (see photo). The upper body tube has the ability to fit the usual 6 numbered objectives (all lenses intact) PLUS an unusual and rare triplet stacking achromatic lens in it's own brass container.

The overall condition is fine and original with over 75% original lacquer with the largest losses on the main body tube (from hand salt and abrasion). The Honduran flame mahogany case has three stable cracks on the lid and the base has been replaced. The original owner did not know how the microscope folded with the mirror wedged between the limb and the folded base, The original partitions were glued in on the opposite side to where they should have been. This situation has been corrected. The case measures 12 x 7 x 3.5" (300 x 180 x 90 mm.). The microscope can stand 16" tall.

The accessories are limited but practical. Although there are holes in the stage for forceps and a bullseye, there are no slots in the case for them. There is a pair of hand forceps, a hand magnifier, a black/white disc and a substage condenser but there is not the usual "fluffy" items. Nowhere to put sliders, a live box, bench condenser, etc, this scope had a specific use (mineralogical?) and is of a very rare transitional form from the first quarter of the 19th century!