d a kind of dissolving cloud, through which now more and more
clearly objects beyond him could be distinguished. Impossible though
this seemed, it was indubitably true.

As he disappeared, he kept speaking. The effect of that undiminished
voice, calm, slow, resonant, issuing from that disintegrating vapor,
stirred the hair on the captive Frenchman's neck and scalp.

"Vibration, _mon cher monsieur_," said he, "is everything. According
to the researches of the Ecole Polytechnique, in Paris--no doubt you,
yourself, have studied there, _n'est-ce pas?_--vibration of the first
octave from 2 to 8 per second, give us no sense-impression. From the
fourth to the fifteenth octave, 16 to 32,768 per second, we get sound.
The qualities of the 16th to the 24th are--or have been, until I
investigated--quite unknown. The 25th to the 35th, 33, 554, 432 to 34,
859, 738, 868 vibrations per second, give us electricity. Thence to
the 45th, again unknown.

"The 4th to the 48th give us heat. The 49th gives light The 50th,
chemical rays, vibrating 1, 125, 899, 906, 842, 624 per second. The
51st to the 57th have never been touched by anyone save myself. The
X-ray group extends from the 58th to the 61st octave. The 62d, with 4,
611, 686, 427, 889, 904 vibrations per second, is a field where only
I have worked. And beyond these, no doubt, other octaves extend with
infinite possibilities.

"You will note, _monsieur_," he continued, while the dun penumbra
still more and more withdrew him from Leclair's sight, "that great
lacunae exist in the scale of vibratory phenomena. Some of the
so-called lower animals take cognizance of vibrations that mean
nothing to us. Insects hear notes far above our dull ears. Ants are
susceptible to lights and colors unseen to our limited eyes. The
emperor-moth calls its mate--so says Fabre--by means of olfactory
vibrations totally uncomprehended by us. The universe is full of hues,
tones, radiant phenomena that escape us, because our senses are not
attuned to them."

Steadily he spoke, and steadily the humming drone that filled the
cabin kept its undertones that lulled, that soothed. The Frenchman,
staring, hardly breathed. Rigid he sat and pale, with sweat now slowly
guttering down his face, his jaws clamped hard and white.

"If the true nature of the universe could suddenly be revealed to our
senses," went on the Master, now hardly more than a dull blur, "we
could not survive. The crash of cosmic sound, the blaz