CONDENSER

n. Ko2n-de2ns'u6r. Lat., con dens at or. Fr., con dens at eur. Ger., Verdichter. It., con dens a tore. Sp., con den sad or. An apparatus for effecting condensation of vapor, light, etc.; of Volta, an electrical accumulator. [L, 30, 41, 44.] Abbe's c. A light-c. which consists of a substage mirror, a diaphragm, and a system of lenses so arranged that the whole apparatus maybe raised and lowered in order to alter the focus. In the diagram, 1 represents the mirror. This has a plane and a convex surface. The latter is only to be used with low power objectives; 2 represents the diaphragm, which is either of the " iris " form or so made that apertures of various sizes may be used; 3 and 4 are the lenses. These are so ground that when a small diaphragm is used, parallel rays will be brought to a focus at a short distance about the upper lens. When, however, no diaphragm is used, the rays are refracted so that the object is illuminated from all sides. All of the image which is produced ABBE'S CONDENSER. by shadow is thus obliterated. Those parts, however, which are colored still show, for the color-image and the form-image are different. The most important use of the c. is this obliteration of the form-image, since it makes po ible the discovery of stained objects which would otherwise be hidden by the structures about them, [a, 28.] Achromatic c. An achromatic lens attached to a microscope to concentrate the rays from the mirror on the object under examination. [B, 77 (a, 24).] Bartlett's c. A combination of a gla retort with a water-jacket, tube, or canister as a c. It is a Liebig's c. applied directly to the neck of a retort, [a, 24.] Borda y Barcell's c. A c. consisting U2, blue; V\ lull; U4, full: U, urn: U, like u (German.) [s. 369]