"Thank heaven, Frank, it's you! I'd given you up ages ago! Meet me the beginning of tomorrow wake at the end of gallery C 341, at the northeast end of Nullnull. Better come disguised. Phil."

Still unable to overcome my astonishment at the prospective reunion with my old friend, whom I had long lamented as lost, I passed a sleepless night; and hours before the brightening camp-lights had announced the beginning of the new "wake," I had risen from bed, disguised myself by means of a steel helmet and a long flowing black robe, and slipped away silently through the wilderness of galleries that tunneled the borderland of Nullnull.

I well knew that the adventure was not without its perils; nevertheless, the hope of seeing Clay again more than sufficed to overcome my fears. Guided by a flashlight, I kept on at a steady pace through the darkness, until at length a welcome sign, stamped in the rock of the cavern wall, informed me that I had reached gallery C 341.

Down this thoroughfare, which wound tortuously, I proceeded at an increasing pace, while my eyes explored the shadows in the hope of encountering a well-known figure. But it seemed as if I had traveled miles before finally the gallery came to a dead end just ahead, and I stopped short, dismayed and baffled. My friend was not to be seen!

Then, as I paused, removing my helmet for the sake of comfort and wondering whether to retrace my steps, a vague shape withdrew from the dimness behind a shelf of rock. At first, amid the blackness of the cavern, illuminated only by my flashlight, the newcomer seemed more like a ghost than a human being; while, startled by his eerie appearance, and by his head and shoulders muffled in a heavy cape, I hesitated to speak.

But, even at that instant, a well-known voice rang through the air: "Frank!"

"Phil!" I called back; and, the next moment, we were gripping each other's hands in a fervent clasp.

I do not know how long we lingered there, bound in that delighted handclasp, or clapping each other on the shoulders with affectionate glee; while, overcome by emotion, we were too greatly stirred for coherent speech.

"Well, old fellow, let's have a look at you!" at last ejaculated Clay, pulling out a flashlight and casting the rays full upon my face. "Say, how you've changed! You're looking like your own grandfather!"

"Years have gone by, you know," I returned, not pleased by this compliment. "Now let's take a glance at you!"