The Microscope: An Introduction to Microscopic Methods and to HistologyComstock publishing Company, 1901 - 299 Seiten |
Häufige Begriffe und Wortgruppen
Abbe achromatic achromatic condenser acid alcohol Amer angle angular aperture apochromatic apparatus appear axial balsam bands Bausch & Lomb camera lucida carbon Carpenter-Dallinger catalog cell cement centimeters collodion color screen compound microscope concave cover cover-glass crystals dark dehydration determined diameter diaphragm distance drawing surface edge embryo equivalent focus eye-lens field focusing screen Fraunhofer lines glycerin high powers histology homogeneous immersion illumination immersion objectives Jour lamp Leitz lenses light lines liquid lower magnification medium method Micr micro micro-spectroscope microscopic objectives microtome millimeters minutes mirror mounted necessary numerical aperture oblique obtained ocular micrometer optic axis opticians ordinary paper paraffin photo-micrographs photographic picric acid plane plate position preparation prism projection ocular rays real image refraction removed satisfactory screw seen shellac side simple microscope sine slide slit solution specimen spectrum stage micrometer stain thickness tion tissue tube tube-length vertical Wetzlar xylene Zeiss
Beliebte Passagen
Seite 53 - ... that the ratio of the sines of the angles of incidence and refraction is constant for refraction in the same medium, was effected by Snell and Descartes.
Seite 41 - Observations. (203.) 1. The eye should be protected from all extraneous light, and should not receive any of the light which proceeds from the illuminating centre, excepting what is transmitted through or reflected from the object. 2. Delicate observations should not be made when the fluid which lubricates the cornea is in a viscid state. 3. The best position for microscopical observations is when the observer is lying horizontally on his back.
Seite 285 - Illustrated Encyclopaedic Medical Dictionary : Being a Dictionary of the Technical Terms used by Writers on Medicine and the Collateral Sciences in the Latin, English, French, and German Languages.
Seite 16 - In order to render comparison accurate between different kinds of objectives, Professor Abbe takes into consideration the rays actually passing from the back combination of the objective to form the real image ; he thus takes into account the medium in front of the objective as well as the angular aperture. The term "numerical aperture...
Seite 15 - By the angular aperture of an objective is meant the "angle contained, in each case, between the most diverging rays issuing from the axial point of an object (ie, a point in the object situated on the optic axis of the microscope), that can enter the objective and take part in the formation of an image
Seite 270 - Nebulous doubling with oblique illumination indicates overcorrection of the marginal zone, want of the edges without marked nebulosity indicates undercorrection of this zone; an alteration of the adjustment for oblique and central illumination, that is, a difference of plane between the image in the peripheral and central portions of the objective points to an absence of concurrent action of the separate zones, which may be due to either an average under- or overcorrection or to irregularity in the...
Seite 198 - Science, 1891, pp. 271-289; Hodge, on nerve cells in rest and fatigue, Jour. Morph., vol. VII. (1892), pp. 95-168; Jour. Physiol., vol. XVII., pp. 129-134; Gage, The processes of life revealed by the microscope ; a plea for physiological histology, Proc. Amer. Micr. Soc., vol. XVII. (1895), pp. 3-29; Science, vol. II., Aug. 23, 1895, pp. 209-218).
Seite 231 - The best light is sunlight. That has the defect of not always being available, and of differing greatly in intensity from hour to hour, day to day, and season to season. The sun does not shine in the evening when many workers find the only opportunity for work. Following the sunlight the electric light is the most intense of the available lights.
Seite 6 - ... the principal axis. The ray OC through the center of the lens goes on undeviated. These two refracted rays...
Seite 55 - ... the milled-head of the fine motion, and move it briskly backwards and forwards in both directions from the first position. Observe the expansion of the dark outline of the object, both when within and when without the focus. If the greater expansion, or coma, is when the object is without the focus, or farthest from the Objective, the lenses must be placed farther asunder, or towards the mark ' uncovered.' If the greater coma is when the object is within the focus, or nearest to the Objective,...