Beck, Conrad, 1864- · London, R. & J. Beck, Ltd. · leaf 30
agm which is placed below the condenser is gradu-ally closed, it excludes more and more of the oblique rays. Fig. 16shows a large solid cone of light of great angle converged upon theobject, the iris diaphragm being fully open. Fig. 17 shows a small-angled cone transmitted by the same condenser,… … Fig. 15.—^No. 3288, AchromaticCondenser.
Microscopy
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