High Frequency Apparatus Page 220

220 HIGH FREQUENCY APPARATUS pieces of iron rod held in tongs and brought together; spot welding of sheet iron may be done if a device is built to provide sufficient pressure at the contacts; a mass of metal may be brought almost to the melting point if placed in a crucible and the terminals inserted; and, in fact, countless other experiments, many of which will suggest themselves to the possessor of the transformer, may be performed. A most effective stage setting is one of dark purple velvet in the form of a cavelike affair. Practically all of the electrical experiments should be performed in semidarkness in order that the effect may be striking. The fusing of copper and zinc rods held in the tongs with the stage dark makes one of the most startling experiments the author has ever beheld.