. The microscope and its revelations. ace A C of the right-angled prism. Of the latter :i portion is also reflected to K byordinary reflection ai J. Tlie hypotenuse A C is cut at suchan angle thai the relied ion from Jcoincides with that from J att he eye point K, 1 hns utilising the secondary reflection to strengthenthe luminosity of the image. The angle G is arranged so that theextreme marginal ray II from the field of the B eye-piece strikesupon I)G at a point just beyond the angle of total reflection, thediffract ion Lands at the limiting angle being faintly discernible atthis edge o
. The microscope and its revelations. ace A C of the right-angled prism. Of the latter :i portion is also reflected to K byordinary reflection ai J. Tlie hypotenuse A C is cut at suchan angle thai the relied ion from Jcoincides with that from J att he eye point K, 1 hns utilising the secondary reflection to strengthenthe luminosity of the image. The angle G is arranged so that theextreme marginal ray II from the field of the B eye-piece strikesupon I)G at a point just beyond the angle of total reflection, thediffract ion Lands at the limiting angle being faintly discernible atthis edge of the field. This angle gives the greatest amount ofliidit hv iinJiiiiii-i/ reflection, short of total reflection. In use, the microscope should be inclined at an angle of 45°. andthe image tbcussed through the eye-piece as usual; the camera isthen placed in position on the eye-piece, and pushed down until theimage of the object is fully and well seen. The drawing papermust be fixed upon a table on a level with the stage immediately. FIG. 226.—Schroders rainrra llN/ida. ln;. 227.—Diagram explaining Schriiders camera lucida. under the camera. The observer will then see the microscopicalimage projecteil on 1 he paper, and the fingers carrying the pencilpoint will lie clearly in view, the ir/tt°either in front or at the side of the microscope. For accuratedrauing. in all a/.imutlis, the drawing paper should of course coin•ide \\ ith the plane of the optical image. When the paper is in itsproper position, the limiting circle of the field of the microscopebe project
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectmicrosc, bookyear1901
