"But it wasn't this laboratory which riveted my attention. No. It was the unexpected creature that perched in the midst of it and seemed to look into my face with unwinking eyes of gold set in a flat reptilian head. This creature moved; its feathers gleamed metallically; I saw its bill open and shut. Distinctly through the ear-phones came a harsh sound, a sound I can only describe by the words _toc-toc, toc-toc_. Then, just as the picture had appeared, it faded, the lights went out, the purring of the motors ceased. "'Yes,' said the Professor, stepping to my side and removing the headpiece, 'the inhabitants of the sub-atomic planet are birds.' "I could only stare at him dumbly. "'I see that astounds you. You are thinking that they lack hands and other characteristics of the _genus homo_. But perhaps certain faculties of manipulation take their place. At any rate those birds are intelligent beings; in some respects, further advanced in science than are we ourselves. Perhaps it would be more exact to say that their scientific investigations and achievements have been along slightly different lines. If such messages I sent them had come to our world from another planet or dimension, how readily they might have been misconstrued, ridiculed or ignored.' The Professor shrugged his shoulders. 'But the beings in this sub-atomic world interpreted my communications without difficulty. "In no time we were conversing with one another through means of a simplified code. I was soon given to understand that their scientists and philosophers had long recognized the fact that their universe was but an atom in an immeasurably greater dimension of existence; yes, and had long been trying to establish contact with it.' The Professor's voice fell. 'And not that alone: they were eager to cooperate with me in perfecting a method of passing from their world to ours! "'Yes,' he cried, 'much of what I have accomplished has been under their advice and guidance; and they on their part have labored; until now'--his eyes suddenly blazed into my fascinated face--'until now, after months of intensive work and experiment, success is nigh, and any day may see the door opened and one of them come through!' "Gentlemen!" cried Milton Baxter, "what more is there to say? I staggered from Professor Reubens' laboratory that afternoon, my head in a whirl. That was on a Monday. "'Come back Thursday,' he said.