Nikola Tesla Books
THE ALTERNATING CURRENT 11 The experiments have their commercial side as well as their purely experimental. Crops may be forced to an early maturity with a marked increase in the flavor and tenderness. Lettuce is particularly susceptible to the influence of the current, while radishes and beets follow closely. For fancy fruits and vegetables the process is productive of results which add materially to the profits ordinarily to be made. Radio Telegraphy and Telephony.-Beyond a doubt, the most popular and the best known application of the oscillatory current is in the field of radio telegraphy and telephony. Every village seems to have one or more amateur wireless telegraphs. The oscillatory current, when vibrating within a certain range of periodicities, sets up electromagnetic waves in the ether if it be sent into an aerial or overhead wire which is insulated from the earth. These waves, which resemble light waves in point of speed but which are quite invisible, are radiated in all directions at a pressure of the radio telegraph key. The apparatus described in this book is admirably adapted for purposes of radio telegraphy and some of the transformers, condensers and spark gaps represent the best and most modern practice in the construction of radio transmitters.
