s
cool against his cheek. For a moment he fought the back-flow of
knowledge into his emptied mind. When it came, the memory of that horror
he had fled from, he started up with a wild thing's swiftness and glared
around pale-eyed into the unchanging dusk. He was alone. Not even a
rustle in the leaves spoke of the tree-folk's presence.

For a moment he stood there alert, wondering what had roused him,
wondering what would come next. He was not left long in doubt. The
answer was shrilling very, very faintly through that aching quiet, an
infinitesimally tiny, unthinkably far-away murmur which yet pierced his
ear-drums with the sharpness of tiny needles. Breathless, he strained in
listening. Swiftly the sound grew louder. It deepened upon the silence,
sharpened and shrilled until the thin blade of it was vibrating in the
center of his innermost brain.

And still it grew, swelling louder and louder through the twilight world
in cadences that were rounding into a queer sort of music and taking on
such an unbearable sweetness that Smith pressed his hands over his ears
in a futile attempt to shut the sound away. He could not. It rang in
steadily deepening intensities through every fiber of his being,
piercing him with thousands of tiny music-blades that quivered in his
very soul with intolerable beauty. And he thought he sensed in the
piercing strength of it a vibration of queer, unnamable power far
mightier than anything ever generated by man, the dim echo of some
cosmic dynamo's hum.

* * * * *

The sound grew sweeter as it strengthened, with a queer, inexplicable
sweetness unlike any music he had ever heard before, rounder and fuller
and more complete than any melody made up of separate notes. Stronger
and stronger he felt the certainty that it was the song of some mighty
power, humming and throbbing and deepening through the twilight until
the whole dim land was one trembling reservoir of sound that filled his
entire consciousness with its throbbing, driving out all other thoughts
and realizations, until he was no more than a shell that vibrated in
answer to the calling.

For it was a calling. No one could listen to that intolerable sweetness
without knowing the necessity to seek its source. Remotely in the back
of his mind Smith remembered the tree-folk's warning, "When Thag calls,
you must answer." Not consciously did he recall it, for all his
consciousness was answering the siren hummi