A separate line led, apparently, to the den, and where this line feeding the Osram lamp passed near a dark storeroom in a corner Craig examined more closely than ever. Seemingly his search was rewarded, for he dived into the dark storeroom and commenced lighting matches furiously to discover what was there.

"Look, Walter," he exclaimed, holding a match so that I could see what he had unearthed. There, in a corner concealed by an old chest of drawers, stood a battery of five storage-cells connected with an instrument that looked very much like a telephone transmitter, a rheostat, and a small transformer coil.

"I suppose this is a direct-current lighting circuit," he remarked, thoughtfully regarding his find. "I think I know what this is, all right. Any amateur could do it, with a little knowledge of electricity and a source of direct current. The thing is eas. . . Read More