As Lee Renaud, burdened with two heavy leather cases, stepped off the train in Adron, Ohio, and made his way toward the station exit, a big bronzed man rushed forward to meet him.

“Good for you, Lee!” and Captain Bartlot reached a hand for one of the cases. “You did what I was counting on—came in time to superintend the copying of that portable of yours for the field radio use. Say, want to go to the hotel first or straight out to the Nardak’s hangar?”

“On to the Nardak!” said Lee. “I couldn’t rest till I saw it, anyway.”

Radio certainly was getting Renaud “somewhere.” Like a magic jinnee of old, it had picked him up by the scruff of the neck, swished him out of a dreamy Gulf Coast village, and landed him in this hustling midwestern city that was famed for its rubber factories and its airship hangar. If radio, to be exact, hadn’t bodily brought him here to Adron, at least it had been the motive power that had gained for him this trip.

“Renaud of the Radio, do you want to go to the Arctic?”

That had been the beginning of it all. A puzzling communication, that, to drop in on a fellow out of mid-air. Later had come another message in explanation. Both were from his friend, Captain Jan Bartlot. He was planning a “mush” into the Arctic by airship, to prospect for gold and other valuables. He had sold his jewel collection for a vast sum, and now the call of adventure was taking him back into a life of exploration. Captain Jan was the type of man whom danger lures as a honey-pot lures bees. A great new gold rush was stirring the Western Hemisphere—a flying rush into Canada’s frozen Arctic on the hunt for that precious metal. A fur-clad adventurer’s discovery of gold-bearing rock in the northern wilds of the Mackenzie Delta had sent men trekking into that frozen land by canoe, by foot, by dog-sled. On his other explorations, Jan Bartlot had followed land trails and sea trails. But now he proposed to follow the air trail up into the Arctic, to take a huge dirigible into that land of storms and snows. It was an expedition fraught with danger, yet one of marvellous practicability——if handled right. Instead of pushing north for many months on a long trek by canoe and sled, prospectors, geologists, mining engineers, mining-syndicate scouts, all the personnel of a vast mining operation could be transported into the north in record time.

For this mammoth gold hunt, the modern surveyor’s implement was to be the camera, and the connecting link between the various scout parties was to be the “voice of radio.”

On a dangerous journey like this, radio operators had to have something besides a nimble brain and mechanical ability; they must needs possess courage, stamina. It was remembrance of the way one Lee Renaud had stood by an injured man aboard a sinking, derelict roof in the Sargon flood that had caused Bartlot to offer the young fellow a chance to go on this wild, wonderful expedition.

In his long explanatory message sent to Renaud at King’s Cove, Bartlot had stated that he wanted to try out the boy’s portable radio model as a connecting link between various mining explorations in the field of operation—was offering five thousand dollars for the right to copy this model and test it, provided Renaud went on the trip. A dangerous test he was offering the young inventor, but if it succeeded—well, it meant world advertising, and the Renaud Portable going over the top, big.

Would Renaud go?