Nikola Tesla Books
THE OSCILLATION CONDENSER 35 55 TINFOIL Fig. 1. Single plate of glass coated on both sides with tin foil order that the high voltage current may be used to store a large amount of energy in a condenser, the dielectric must be made of some material possessed of exceptionally good insulating qualities. Glass and mica are perhaps the best adapted to the purpose of the amateur builder. An air condenser is good as is also a condenser the plates of which are held in a tank of oil; these latter types are difficult and expensive to build, however, and they are, moreover, very cumbersome and heavy. For permanent installations, where the apparatus need not be moved about, a modification of the latter type is excellent. By building first an ordinary glass plate condenser and then immersing it bodily into a tank of oil, all brush discharges, which represent leakage and waste, are eliminated. For most purposes of the amateur or experimenter, however, the simple glass plate condenser is quite satisfactory. Old photographic negatives of the 8 by .10 in. size may be had for the asking in many professional photographers' establishments. This glass is of the finest quality available in the open market, and it is certainly to be preferred to the ordinary window glass that is frequently used for that purpose. If the 8 x 10 negative glasses are coated on both sides with tin foil cut into 6 x 8 in. pieces, each plate or separate
