. The London, Edinburgh and Dublin philosophical magazine and journal of science. pen end a of resonator1 is repelled from K; theclosed end b of resonator 2is attracted : but in generalthis attraction does not in-crease the rapidity of rota-tion, because it counteractsrotation the moment the re-sonator (2) has changed itsposition about 45°. It istherefore not possible to ob-tain continuous rotation bymeans of acoustic attraction,as I have shown by numerous experiments*. The resonator (1) continues to move by reason of its inertia, and resonator (2) takes its place, being in turn repelled, and
. The London, Edinburgh and Dublin philosophical magazine and journal of science. pen end a of resonator1 is repelled from K; theclosed end b of resonator 2is attracted : but in generalthis attraction does not in-crease the rapidity of rota-tion, because it counteractsrotation the moment the re-sonator (2) has changed itsposition about 45°. It istherefore not possible to ob-tain continuous rotation bymeans of acoustic attraction,as I have shown by numerous experiments*. The resonator (1) continues to move by reason of its inertia, and resonator (2) takes its place, being in turn repelled, and so on. A very rapid rotation is obtained by using a large Kundtstube and placing a small acoustic mill before its open end. The glass tube (Kundts), which vibrates longitudinally andproduces the tone, is fastened to a heavy table, and protrudesonly a short distance through the cork into the glass tube,placed upon a separate table so that its open end projectssomewhat beyond the edge of the latter. The length of therod was 127 centims., the diameter 27 millims.; the half wave-. length of its note, ^, equals 10J centims. The length of the tube was 45 centims.; the length of the vibrating column ofair, corrected for the open end, was 3 « -f- j ; the inner dia-meter was 5 centims. * Instead of the resonators (fig. 3) I used vertical paper vanes, varyinge curvature, without achieving any results, notwithstanding the fact thatthere was a pretty strong acoustic attraction for each separate vane. M. Dvorak on Acoustic Repulsion. 229 3. The Acoustic Torsion-balance.—If we hang by a wire awooden rod provided with a resonator, like the beam of aCoulombs torsion-balance, in a case having an opening in theside turned toward the resonator, we can compare the inten-sity of notes having an equal number of vibrations by meansof the repulsion of the resonator ; but further experiments arenecessary to test the practicability of this method. The soundproceeded from an open pipe, having the not
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