Carpenter, William Benjamin, 1813-1885, Dallinger, W. H. (William Henry), 1842-1909 · Philadelphia, Blakiston · leaf 316
ed to express dissatisfaction with its performance. 3. Messrs. R. and J. Beck, in place of a speculum pierced,employ a disc of cover-glass. The cover-glass is mounted on apin, B, fig. 240, in order that it may be rotated and oblique lightobtained by the milled head, / A, fig. 240. We believe that… … Fig. 239. Fig. 240. 4. Powell and Lealands method is to fix a piece of glass, work/flat, at an angle of 45° to the optic axis, with a rotating diaphragmin front of the aperture admitting the light. To use these instruments the edge of the lamp flame should beplaced in front of the reflector, so…
Microscopy
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