Nikola Tesla Books
CHAPTER XX. THE CONSTRUCTION OF A WELDING TRANSFORMER. While this piece of apparatus can scarcely be placed in the category of high frequency apparatus, since the current employed is the ordinary 25, 60, or 125 cycle lighting current, still the welding transformer forms a valuable addition to the high potential apparatus used in an electrical offering on the stage. The feat of grasping a piece of iron wire, as thick as a pencil, between two pairs of tongs held in the hands and causing the wire to become red and even white hot while held in that position, is a stunt which seldom fails to call forth the applause of an audience. When the experiment is conducted with the proper scenic atmosphere, the effect is materially enhanced. In this chapter the reader will find the details of the construction of a low-voltage transformer admirably adapted to this purpose. The transformer can be built by the average handyman who has a smattering of electrical knowledge and who knows the value of careful work as regards insulation Later in the chapter, the design of a suitable stage setting and accessories will be described. While this experiment may readily be made one of a number grouped up into a single offering, still it is quite complete in itself and with embellishments, it may form the basis for an act of a few minutes' duration. In order to make the description clearer, the various parts of the transformer will be described separately, each 212
