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 easily constructed, the materials are common, and a wonderfully complicated result can be obtained. What's this?"
He had continued to poke about in the darkness as he was speaking. In another corner he had discovered two ordinary telephone receivers.
"Connected up with something, too, by George!" he ejaculated.
Evidently some one had tapped the regular telephone wires running into the house, had run extensions into the little storeroom, and was prepared to overhear everything that was said either to or by those in the house.
Further examination disclosed that there were two separate telephone systems running into Brixton's
