Experimental science. Elementary, practical and experimental physics (1890)
Hopkins, George M. (George Milton), 1842-1902 · New York, Munn & co. · leaf 319
xhibited tosome extent by an apertured disk, like that above described,twirled by the thumb and finger or revolved like a top bymeans of a string; or by using a larger apertured diskfitted to a rotator, and placed between the source of lightand the mirror of the microscope. 296 EXPERIMENTAL… … Simple Frog Plate. Among animal organisms, the daphnia, or water flea, isextremel}^ interesting, the minute heart being made clearlyvisible by the transparency of the shell of this little creature. Fig. 306.
Physics · Lantern projection · Electric apparatus and appliances
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