Pillischer’s Microscopes.
Mr. Pillischer (New Bond Street) is favourably known for the excellency of his instruments. He has lately brought out several microscopes of an improved form. His larger model, the “New International,” consists of a solid, well-built, firm tripod stand of the Ross-Jackson pattern, which appears to be quite in the ascendant among London opticians; rack and pinion coarse adjustment, and a superior micrometer fine adjustment; sub-stage with centring screws and rack and pinion focussing adjustment; a new form of sliding pin-hole diaphragm and iris diaphragm; B and C eye-pieces; 5⁄8 and 1⁄7 objectives; Abbe condenser, N.A. 1·20; in every respect a perfect model, neatly packed in a mahogany case, for a very moderate sum. Mr. Pillischer’s No. 2 ([Fig. 93]) “International” Microscope, being the Army pattern as well as the student’s, is well adapted for clinical work. A firm tripod stand supports two dark bronze uprights, with rack and pinion coarse adjustment, e, and fine adjustment, d, the stage, i, is wide and suitable for clinical work, and large enough for dissecting upon. The whole instrument is well made; the coarse adjustment is so good that the one-eighth inch can be focussed with ease, and without using the fine adjustment.
For a few shillings extra, a mechanical stage can be added, consisting of levers, having an action similar to the movements of a parallel ruler, which is so easy of adjustment that it can be worked under the eighth-inch objective with the hands—an advantage in a clinical microscope.
Fig. 93.—Pillischer’s “International” Microscope.
The following reference letters serve to explain the general construction of the microscope ([Fig. 93]):—a, the eye-piece; b, the draw-tube; c, the sliding-tube; d, micrometer or fine adjustment; e e, the coarse adjustment; g, the mirror arm and mirror; h, sub-stage carrying Abbe condenser; i, the stage with spring-clips; j, objectives screwed into place and double nose-piece.
The “Kosmos” is Pillischer’s cheaper model. The stand of this somewhat novel and original microscope is framed entirely of brass and gun-metal. The fine adjustment is very sensitive and perfectly steady, admitting of the highest immersion objectives being used. The optical parts are constructed upon principles consistent with the latest improvements. It has a claw-foot stand with a semi-circular arm, which carries the body, with sliding-tube coarse adjustment, and micrometer screw fine adjustment, with a large square stage diaphragm and mirror. The instrument is neatly packed in a mahogany box, together with the A or B eye-piece, 1-inch and 1⁄5-inch objectives of good defining and penetrating power, magnifying from 30 to 380 diameters, in mahogany cabinet, for the moderate sum of £5.
Pillischer’s Binocular Microscope ([Fig. 94]) is constructed on a plan somewhat intermediate between that of Beck’s and Ross’s well-known patterns, and in point of finish is equal to any student’s microscope in use. The semi-circular form given to the arm carrying the body increases the strength and solidity of the instrument, although it is doubtful whether it adds to its steadiness when placed in the horizontal position. The straight body rests for a great part of its length upon a parallel bar of solid brass ploughed into which is a groove for the reception of the rack attached to the body, the groove being of such a form that the rack is held firmly while the pinion glides smoothly through it. A steady, uniform motion is thus obtained, which almost renders the fine adjustment unnecessary. The binocular bodies are inclined at a smaller angle to one another than in most instruments; nevertheless, the range of motion given to the eye-pieces by the rack and pinion enables those whose eyes are widely separated to use the instrument with comfort. The prism is so well set that it illuminates both fields with equal intensity. The stage is provided with rectangular traversing movements to the extent of an inch and a quarter in each direction. The milled heads which effect these are placed on the same axis, instead of side by side, one of them—the vertical one—being repeated on the left of the stage, so that the movements may be communicated either by the right hand alone or by both hands acting in concert. The stage-plate has the ordinary vertical and rotatory motions, but to a much greater extent than usual; and the platform which carries the object is provided with a spring clip to secure the object when the stage is placed in the vertical position. A new form of sub-stage with centring screws is made to carry the Abbe achromatic condenser, diaphragm, polarising and other apparatus.
Fig. 94.—Pillischer’s Binocular Microscope.