A1 Congress patent May 27, 1879, with all the latest improvements. Binocular mechanical stage, concentric; adjustable to the optic axis; swinging substage and mirror; broad gauge screw for wide angle; low powers; safety nosepiece with Society screw; rack and pinion coarse motion, lever slow motion moving the whole body; adjustable substage, revolving with rack and pinion. The stage, substage, mirror, base, and side of body tube are graduated. Iris and Gillet diaphragm, 5 eyepieces..........$300

Professional Stand, patent 1879, 16 inches high when arranged for use; swinging substage and mirror, can be used over the stage; rack and pinion coarse motion; lever slow motion, moving the whole body; London Society screw, also the broad gauge screw; sliding glass stage, has complete revolution and is adjustable; single pillar and tripod base; Gillet diaphragm, 2 eyepieces and case........$90

Biological Stand patent 1879; 12 1/2 inches high when arranged for use; stage 3 1/2 inches from table when in a horizontal position; tube 5 inches long, but with draw to 9 inches; rack and pinion coarse motion; lever fine motion, moving the whole body; single pillar and tripod base; stand all brass; plain stage, with spring clips. Diaphragm, substage and mirror each swing over stage.
Biological Stand, 1 eyepiece and case..............$40