Age: 1750–1800
Made by: Unknown
Made in: probably Holland
Large Dutch Double Microscope (No. 41)
Mechanics
Imaging
This is a very large compound microscope probably of Dutch origin. The instrument is supported by a massive curved tripod leg system bolted to a circular support pillar. The microscope body is screwed into a flat brass cantiliver which is itself screwed into the top of the main support pillar. The bolt holding these two pieces together is a decorative brass topknot. The microscope body is large enough to resemble a telescope, except for the small conical end to which the objective is attached. The body tube is brass and is covered with red tooled leather. The optics of the instrument consist of an eye and field lens mounted in a brass drawtube and a single low magnification objective lens. The friction collar of the drawtube screws into the distal end of the body tube. Hand cutouts in the collar function to add friction to the movement of the drawtube. Focus of the sample stage is via rack & pinion, with the rack machined into a square shaft fastened at the top to the cantilever and at the bottom to the base of the support pillar. Also attached to the shaft is the mirror assembly which slides up or down. For epi-illumination of opaque samples this microscope has a large bullseye lens attached to the cantilever via a ball joint. Imaging using the existing objective yields approximately 100x and suffers from poor contrast due, in part, to the lack of any light condensing system. The microscope is approximately 66cm tall.

This microscope was featured 12/2012