He says the idea was suggested to him by the vagaries of static and in groping around in search of some device to eliminate this he discovered in the ether an undercurrent that operated according to no previously known scientific laws.

At his Tarzana home he has erected a station and a few miles away, at the back of my ranch, another. Between these stations we talk to one another through some strange, ethereal medium that seems to pass through all other waves and all other stations, unsuspected and entirely harmless—so harmless is it that it has not the slightest effect upon Jason's regular set, standing in the same room and receiving over the same aerial.

But this, which is not very interesting to any one except Jason, is all by the way of getting to the beginning of the amazing narrative of the adventures of Tanar of Pellucidar.

Jason and I were sitting in his "lab" one evening discussing, as we often did, innumerable subjects, from "cabbages to kings," and coming back, as Jason usually did, to the Gridley Wave, which is what we have named it.

Much of the time Jason kept on his earphones, than which there is no greater discourager of conversation. But this does not irk me as much as most of the conversations one has to listen to through life. I like long silences and my own thoughts.

Presently, Jason removed the headpiece. "It is enough to drive a fellow to drink!" he exclaimed.

"What?" I asked.

"I am getting that same stuff again," he said. "I can hear voices, very faintly, but, unmistakably, human voices. They are speaking a language unknown to man. It is maddening."

"Mars, perhaps," I suggested, "or Venus."

He knitted his brows and then suddenly smiled one of his quick smiles. "Or Pellucidar."

I shrugged.

"Do you know, Admiral," he said (he calls me Admiral because of a yachting cap I wear at the beach), "that when I was a kid I used to believe every word of those crazy stories of yours about Mars and Pellucidar. The inner world at the earth's core was as real to me as the High Sierras, the San Joaquin Valley , or the Golden Gate, and I felt that I knew the twin cities of Helium better than I did Los Angeles .