From the catalog of August Stendicke, New York:
      Illustrated & Descriptive Catalogue of Optical
      Instruments c.1890
    
    
                THE
                INVESTIGATOR MICROSCOPE
              
              
                In this stand I confidently claim to have reached a
                higher degree of perfection than is possessed by
                anyone approximating it in price. It combines, in a
                moderate-priced instrument, the features of a
                first-class and high-priced stand at no sacrifice
                of its working qualities. The different parts are
                ingeniously combined, are strong and firm, and in
                the parts subject to friction I have introduced, as
                much as possible, new compensating bearings, which
                enable the instrument to endure any amount of work
                and still retain smooth and reliable movements,
                Working microscopists will understand the value of
                this quality. When contracted, it stands but 11
                inches high, but can be extended to 18 inches.
              
              
                The base is of brass, and has the tripod form:
                pillar and arm of brass, connected by a solid
                joint, which allows inclination of body to any
                angle; rack and pinion for coarse adjustment, fine
                adjustment by our patent frictionless motion; main
                tube, with two draw tubes. This is an entirely new
                feature in Microscopes, which is an unquestionable
                improvement. It permits the use of standard length
                of tube for quick adjustment ill outside tube, same
                as in instruments without rack and pinion
                adjustment; the same for any low power objective
                and the use of amplifier in either combination. The
                outside tube has a broad gauged screw, and adapter
                with society screw. The stage lies in the same
                plane as centre of movement for mirror, is of
                brass, and has concentric, revolving motion with
                removable clips. It is thin to allow great
                obliquity, and, as it rests upon a strong
                projecting arm, is perfectly firm under any
                manipulation.
              
              
                The mirror-bar swings with a perfectly easy but
                firm motion, upon one bearing to any obliquity
                below, and above the stage for the illumination of
                opaque objects, and has affixed to it a secondary
                bar, to which the mirror is attached and which
                allows the separate use of the latter in any
                position of the sub-stage. It is provided with a
                sliding arrangement, whereby the mirror may be
                moved to and from the object. The mirrors are plain
                and concave, and of large size. The sub-stage is
                adjustable along the mirror-bar and entire
                removable. It contains a diaphragm which may be
                brought directly under the stage. The ring is of
                standard size and is easily centered by a
                set-screw. Steel pin for centering stage and
                sub-stage accompanies the instrument.
              Eye-pieces A and C, the latter arranged with slot
              for micrometer. Objectives, 3-4 inch and 1-5
              inch.
              Camera lucida, eye-piece micrometer, pliers, slides
              and covers. Magnifying powers, 35 to 600
              diameters.
              In upright walnut case, with handle and lock, drawer
              for accessories, and receptacles for eye-pieces and
              objectives,  - $70.00
              The above, when double nose-piece is ordered with it,
              - 75.00
              Same stand, with any power eye"piece, in above
              case,  - 45.00
              The above, with improved glass stage and slide
              carrier, which fastens to the brass stage, extra, -
              5.00