The inventions : researches and writing of Nikola Tesla, with special reference to his work in polyphase currents and high potential lighting (1894)
Martin, Thomas Commerford, 1856-1924, Tesla, Nikola, 1856-1943 · New York : The Electrical Engineer · leaf 395
g the rate of change in thecurrent, and consequently the number of vibrations per unit oftime of the gaseous material of the arc u]) to, or beyond, tentliousand or eleven thousand per second, or to what is regardedas the limit of audition, tlie sound due to sucli vibrations will notbe audible. The… … Figs. 200, 20]. 202 nnd 203. numbei ot clianges tiiat will he r((|iiii-(il to i-eiider it inaudiblewithin certain limits. It should also be stated that the arc shouhlnot exceed a certain length. The difficulties encountered in the construction of tliesemachines are of a mechanical as well as an…
Electric currents, Alternating · Electrical engineering
Internet Archive · Gerstein Library, University of Toronto · Public Domain Mark 1.0. Free to use for anything.
![An illustration from [Graphophone patents] (1878)](https://img.insideoutlibrary.com/img/200/ia-graphophonepaten07unit-897-577.webp)
