Necronomicon- Powder to Kill the Dunwich Horror

At other times he would call for the dreaded Necronomicon and the Daemonolatreia of Remigius, in which he seemed hopeful of finding some formula to check the peril he conjured up.
     “Stop them, stop them!” he would shout. “Those Whateleys meant to let them in, and the worst of all is left! Tell Rice and Morgan we must do something—it’s a blind business, but I know how to make the powder. . . . It hasn’t been fed since the second of August, when Wilbur came here to his death, and at that rate. . . .”
...

We must follow it, boys.” He made his voice as reassuring as possible. “I believe there’s a chance of putting it out of business. You men know that those Whateleys were wizards—well, this thing is a thing of wizardry, and must be put down by the same means. I’ve seen Wilbur Whateley’s diary and read some of the strange old books he used to read; and I think I know the right kind of spell to recite to make the thing fade away. Of course, one can’t be sure, but we can always take a chance. It’s invisible—I knew it would be—but there’s a powder in this long-distance sprayer that might make it shew up for a second. Later on we’ll try it. It’s a frightful thing to have alive, but it isn’t as bad as what Wilbur would have let in if he’d lived longer. You’ll never know what the world has escaped. Now we’ve only this one thing to fight, and it can’t multiply. It can, though, do a lot of harm; so we mustn’t hesitate to rid the community of it.
...

Then Wesley Corey, who had taken the glass, cried out that Armitage was adjusting the sprayer which Rice held, and that something must be about to happen. The crowd stirred uneasily, recalling that this sprayer was expected to give the unseen horror a moment of visibility. Two or three men shut their eyes, but Curtis Whateley snatched back the telescope and strained his vision to the utmost. He saw that Rice, from the party’s point of vantage above and behind the entity, had an excellent chance of spreading the potent powder with marvellous effect.
     Those without the telescope saw only an instant’s flash of grey cloud—a cloud about the size of a moderately large building—near the top of the mountain. Curtis, who had held the instrument, dropped it with a piercing shriek into the ankle-deep mud of the road. He reeled, and would have crumpled to the ground had not two or three others seized and steadied him. All he could do was moan half-inaudibly,
     “Oh, oh, great Gawd . . . that . . . that . . .”
     There was a pandemonium of questioning, and only Henry Wheeler thought to rescue the fallen telescope and wipe it clean of mud. Curtis was past all coherence, and even isolated replies were almost too much for him.
     “Bigger’n a barn . . . all made o’ squirmin’ ropes . . . hull thing sort o’ shaped like a hen’s egg bigger’n anything, with dozens o’ legs like hogsheads that haff shut up when they step . . . nothin’ solid abaout it—all like jelly, an’ made o’ sep’rit wrigglin’ ropes pushed clost together . . . great bulgin’ eyes all over it . . . ten or twenty maouths or trunks a-stickin’ aout all along the sides, big as stovepipes, an’ all a-tossin’ an’ openin’ an’ shuttin’ . . . all grey, with kinder blue or purple rings . . . an’ Gawd in heaven—that haff face on top! . . .”
...

Without warning came those deep, cracked, raucous vocal sounds which will never leave the memory of the stricken group who heard them. Not from any human throat were they born, for the organs of man can yield no such acoustic perversions. Rather would one have said they came from the pit itself, had not their source been so unmistakably the altar-stone on the peak. It is almost erroneous to call them sounds at all, since so much of their ghastly, infra-bass timbre spoke to dim seats of consciousness and terror far subtler than the ear; yet one must do so, since their form was indisputably though vaguely that of half-articulate words. They were loud—loud as the rumblings and the thunder above which they echoed—yet did they come from no visible being. And because imagination might suggest a conjectural source in the world of non-visible beings, the huddled crowd at the mountain’s base huddled still closer, and winced as if in expectation of a blow.
     “Ygnaiih . . . ygnaiih . . . thflthkh’ngha . . . Yog-Sothoth . . .” rang the hideous croaking out of space. “Y’bthnk . . . h’ehye—n’grkdl’lh. . . .”
     The speaking impulse seemed to falter here, as if some frightful psychic struggle were going on. Henry Wheeler strained his eye at the telescope, but saw only the three grotesquely silhouetted human figures on the peak, all moving their arms furiously in strange gestures as their incantation drew near its culmination. From what black wells of Acherontic fear or feeling, from what unplumbed gulfs of extra-cosmic consciousness or obscure, long-latent heredity, were those half-articulate thunder-croakings drawn? Presently they began to gather renewed force and coherence as they grew in stark, utter, ultimate frenzy.
     “Eh-ya-ya-ya-yahaah—e’yayayayaaaa . . . ngh’aaaaa . . . ngh’aaaa . . . h’yuh . . . h’yuh . . . HELP! HELP! . . . ff—ff—ff—FATHER! FATHER! YOG-SOTHOTH! . . .”
     But that was all. The pallid group in the road, still reeling at the indisputably English syllables that had poured thickly and thunderously down from the frantic vacancy beside that shocking altar-stone, were never to hear such syllables again. Instead, they jumped violently at the terrific report which seemed to rend the hills; the deafening, cataclysmic peal whose source, be it inner earth or sky, no hearer was ever able to place. A single lightning-bolt shot from the purple zenith to the altar-stone, and a great tidal wave of viewless force and indescribable stench swept down from the hill to all the countryside. Trees, grass, and underbrush were whipped into a fury; and the frightened crowd at the mountain’s base, weakened by the lethal foetor that seemed about to asphyxiate them, were almost hurled off their feet. Dogs howled from the distance, green grass and foliage wilted to a curious, sickly yellow-grey, and over field and forest were scattered the bodies of dead whippoorwills.

- The Dunwich Horror, parts VIII, IX and X