From the Illustrated Price List of Microscopes for Sale by T. H. McAllister Manufacturing Optician, No. 49 Nassau Street, New York 1876

Elsewhere on this website is a similar microscope made by Pike.

T. H. McAllister's

Professional Microscope

Has been highly approved by all who have used it, as it combines many advantages not heretofore found in any but the highest priced instruments.

The Professional Microscope stands fifteen inches high when inclined as shown in the engraving the base is of brass, with uprights to receive the axis, upon which the body inclines to any convenient angle. The body is of brass, finely finished with extension draw-tube.

The coarse adjustment for focus is by a delicate watch chain, controlled by a large milled head on each side of the tube; far more efficient and precise than the majority of Rack movements, and will readily adjust the focus for all except the very highest magnifying powers. The fine adjustment for focus is by a very delicate Micrometer Screw acting directly upon the body of the instrument, and moving the entire optical system vertically; free from the irregular lateral movement so often inseparable from an adjustment acting only on the Objective.

The Stage is large and steady, but at the same time thin, allowing facility for extreme obliquity of illumination. To the upper surface a Plate Glass Stage is attached, which can be freely moved in a vertical or horizontal direction to any desirable extent, and can also be revolved. The motion of this Plate Glass Stage is so delicate and simple, that many experienced microscopists prefer it to the elaborate screw stage. A movement as minute as 1-12000 inch can be selected by it. A brass rest with springs to hold the object, is clamped to it, but can be removed in a moment, leaving a clean glass plate for examination of recent anatomical preparations, chemicals, or other substances which would injure the usual Brass Stage. Beneath the Stage is a separable collar carrying the Diaphragm, and also adapted to receive the Polarizer, Parabolic Illuminator, and other accessories.

The Concave and Plain Mirrors are mounted with universal motion, and slide on a jointed bar for direct or oblique illumination.

The mounting for the Objectives is made with the " London Society Screw," so that the Objectives of all first-class makers, can be used with the instrument.