“Here it is. Bender, Silas Bender. 1453 Mission Street. Let’s ask the chauffeur how far away that is.”

After a little discussion, it developed the address given—on the first street paralleling Market to the south—lay on the route to Golden Gate Park,

the Cliff House and Seal Rocks, whither the boys wanted to go. Accordingly, all piled into the car and sped away.

Mr. Bender maintained a little equipment store supplying radio apparatus. The shop was empty of customers when the boys arrived, and, at the ringing of the bell on their entrance, a medium-sized man, brisk and alert, came from the rear room outfitted as workshop. His thinning hair was rumpled. He was in his shirt sleeves.

“What can I do for you, gentlemen?” he asked inquiringly.

Jack stepped forward.

“Are you Mr. Bender?”

“I am.”

“Well, I’m Jack Hampton,” said Jack, extending his hand. “Here’s a note from my father. I believe you have met him.”

“Mr. Hampton the engineer?”