A Manual Of Photography

1852.] GRIFFIN’S SCIENTIFIC CIRCULAR. 107 MICROSCOPES. ACHROMATIC MICROSCOPE, No. 2791. The Microscopes described in the following list, are principally of FRENCH Forms. We have described in the Scientific Circular (No. 4, p. 57), a variety of English Patterns of Microscopes, Simple, Compound, and Achromatic. In the same number, at page 63, we have given a Catalogue of Microscopic Objects. 2791. Compound Achromatic Microscope, with body so constructed that it can be used either vertically or horizontally ; sliding coarse adjustment, tangent screw fine adjustment, two eye-pieces, three sets of achromatic object glasses, achromatic condenser, three movable diaphragms, condenser mounted on foot, concave and plain mirror, fine screw movable stage, micrometer eye-piece, stage micrometer, forceps, needle, knife ; camera lucida, by which a drawing of any object under examination can easily be made ; the whole enclosed in a polished mahogany cabinet with lock and key (fig. 2791), 16L. 16s. 2792. Compound Achromatic Microscope with tripod foot, and jointed pillar, so that the body can be inclined at any angle, concave and plane mirror, revolving diaphragm to stage, two eye-pieces, two sets of Achromatic object glasses, two simple lenses, condenser fitted to stage, for the examination of opaque objects, forceps, needles, and knife for dissections, stage forceps and animalculæ box ; the whole enclosed in a polished mahogany cabinet with lock and key, 8I. 8s. The lenses of this Microscope are adapted for the investigation of the changes of structure by disease, and are equally applicable to the researches of the physio- logist, the botanist, or the amateur. The highest combination of lenses shows the marking on the scales of the Podura Plumbea.