Nikola Tesla Patents
It should be stated before, in regard to the sensitive devices above mentioned, which may be broadly considered as belonging to one class --ina smuch as the operation of all of them involves the breaking down of a minute thickness of highly strained dielectric-- that it is necessary to make some provision for restoring to the dielectric automatically its original, unimpaired insulating qualities in order to enable the device being used in successive operations. This is usually accomplished by a gentle tapping or vibration of the electrodes or particles, or continuous rotation of the same, but in long experience with many forms of these devices I have found that such procedures, while suitable in simple and comparatively unimportant operations, as ordinary signalling, when it is merely required that the succeeding effects produced in the receiving circuit should differ in regard to their relative duration only --in which case it is of little or no consequence if some of the individual effects be altered, or incomplete, or even entirely misseddo not yield satisfactory results in many instances, when it may be very important that the effects produced should all be exactly such as desired and that none should fail. To illustrate, let it be supposed that an official, directing the movements of a vessel in the manner described, should find it necessary to bring into action a special device on the latter, or to perform a particular operation, perhaps of vital moment, at an instant's notice and possibly when, by design or accident, the vessel itself or any mark indicating its presence is hidden from his view. In this instance a failure or defective action of any part of the apparatus might have dis(9) 233
