Nikola Tesla - Free-Energy Devices

140 INVENTIONS OF NIKOLA TESLA.Tesla has found tlmt the deterioration of the electrode is the less,the higher the frequency. This was to be expected, as then theheating is effected by many small impacts, instead by fewer andmore violent ones, which quickly shatter the structure. The deteriorationis also smaller when the vibration is harmonic. Thusan electrode, maintained at a certain degree of heat, lasts muchlonger with currents obtained from an alternator, than withthose obtained by means of a disruptive discharge.One of themost durable electrodes was obtained from strongly compressedcarborundum, which is a kind of carbon recently produced byMr. E. G. Acheson, of Monongahela City, Pa. From experience,it is inferred, that to be most durable, the electrode shouldbe in the form of a sphere with a highly polished surface.In some bulbs refractory bodies were mounted in a carbon cupand put under the molecular impact. It was observed insuch experiments that the carbon cup was heated at first, until ahigher temperature was reached; then most of the bombardmentwas directed against the refractory body, and the carbonwas relieved. In general, when different bodies were mountedin the bulb, the hardest fusible would be relieved, and wouldremain at a considerably lower temperature. This was necessitatedby the fact that most of the energy supplied would findits way through the body \vhioh was more easily fused or "evaporated."Curiously enough it appeared in some of the experimentsmade, that a body was fused in a bulb under the molecular impactby evolution" of less light than when fused by the applicationof heat in ordinary ways. This may be ascribed to aloosening of the structure of the body under the violent impactsand changing stresses.Some experiments seem to indicate that under certain conditionsa body, conducting or nonconducting, may, when bombarded,emit light, which to all appearances is due to phosphorescence,but may in reality be caused by the incandescence of aninfinitesimal layer, the mean temperature of the body beingcomparatively small. Such might be the case if each singlerhythmical impact were capable of instantaneously exciting theretina, and the rhythm were just high enough to cause a continuousimpression in the eye. According to this view, a coil operatedby disruptive discharge would be eminently adapted to producesuch a result, and it is found by experience that its power of