to assure me that there could be no slightest grain of truth or
possibility in your wild tale--it was fiction pure and simple.

And yet where WERE the other ends of those wires?

What was this instrument--ticking away here in the great Sahara--but
a travesty upon the possible!

Would I have believed in it had I not seen it with my own eyes?

And the initials--D. I.--upon the slip of paper!

David's initials were these--David Innes.

I smiled at my imaginings. I ridiculed the assumption that there
was an inner world and that these wires led downward through the
earth's crust to the surface of Pellucidar. And yet--

Well, I sat there all night, listening to that tantalizing clicking,
now and then moving the sending-key just to let the other end know
that the instrument had been discovered. In the morning, after
carefully returning the box to its hole and covering it over with
sand, I called my servants about me, snatched a hurried breakfast,
mounted my horse, and started upon a forced march for Algiers.

I arrived here today. In writing you this letter I feel that I am
making a fool of myself.

There is no David Innes.