was basically the idea of a very color that appeared that was so bizarre and undefinable that the narrator's friends were shaking and starting to gibber with madness. Here's a section that about defines what Lovecraft's all about, in regards to the themes of scary unknown things:
"So the men paused indecisively as the light from the well grew stronger and the hitched horses pawed and whinnied in increasing frenzy. It was truly an awful moment; with terror in that ancient and accursed house itself, four monstrous sets of fragments?two from the house and two from the well?in the woodshed behind, and that shaft of unknown and unholy iridescence from the slimy depths in front. Ammi had restrained the driver on impulse, forgetting how uninjured he himself was after the clammy brushing of that coloured vapour in the attic room, but perhaps it is just as well that he acted as he did. No one will ever know what was abroad that night; and though the blasphemy from beyond had not so far hurt any human of unweakened mind, there is no telling what it might not have done at that last moment, and with its seemingly increased strength and the special signs of purpose it was soon to display beneath the half-clouded moonlit sky.
All at once one of the detectives at the window gave a short, sharp gasp. The others looked at him, and then quickly followed his own gaze upward to the point at which its idle straying had been suddenly arrested. There was no need for words. What had been disputed in country gossip was disputable no longer, and it is because of the thing which every man of that party agreed in whispering later on that the strange days are never talked about in Arkham. It is necessary to premise that there was no wind at that hour of the evening. One did arise not long afterward, but there was absolutely none then. Even the dry tips of the lingering hedge-mustard, grey and blighted, and the fringe on the roof of the standing democrat-wagon were unstirred. And yet amid that tense, godless calm the high bare boughs of all the trees in the yard were moving. They were twitching morbidly and spasmodically, clawing in convulsive and epileptic madness at the moonlit clouds; scratching impotently in the noxious air as if jerked by some alien and bodiless line of linkage with subterrene horrors writhing and struggling below the black roots.
Not a man breathed for several seconds. Then a cloud of darker depth passed over the moon, and the silhouette of clutching branches faded out momentarily. At this there was a general cry; muffled with awe, but husky and almost identical from every throat. For the terror had not faded with the silhouette, and in a fearsome instant of deeper darkness the watchers saw wriggling at that treetop height a thousand tiny points of faint and unhallowed radiance, tipping each bough like the fire of St. Elmo or the flames that came down on the apostles? heads at Pentecost. It was a monstrous constellation of unnatural light, like a glutted swarm of corpse-fed fireflies dancing hellish sarabands over an accursed marsh; and its colour was that same nameless intrusion which Ammi had come to recognise and dread. All the while the shaft of phosphorescence from the well was getting brighter and brighter, bringing to the minds of the huddled men a sense of doom and abnormality which far outraced any image their conscious minds could form. It was no longer shining out, it was pouring out; and as the shapeless stream of unplaceable colour left the well it seemed to flow directly into the sky.
The veterinary shivered, and walked to the front door to drop the heavy extra bar across it. Ammi shook no less, and had to tug and point for lack of a controllable voice when he wished to draw notice to the growing luminosity of the trees. The neighing and stamping of the horses had become utterly frightful, but not a soul of that group in the old house would have ventured forth for any earthly reward. With the moments the shining of the trees increased, while their restless branches seemed to strain more and more toward verticality. The wood of the well-sweep was shining now, and presently a policeman dumbly pointed to some wooden sheds and bee-hives near the stone wall on the west. They were commencing to shine, too, though the tethered vehicles of the visitors seemed so far unaffected. Then there was a wild commotion and clopping in the road, and as Ammi quenched the lamp for better seeing they realised that the span of frantic greys had broke their sapling and run off with the democrat-wagon.
The shock served to loosen several tongues, and embarrassed whispers were exchanged. ?It spreads on everything organic that?s been around here,? muttered the medical examiner. No one replied, but the man who had been in the well gave a hint that his long pole must have stirred up something intangible. ?It was awful,? he added. ?There was no bottom at all. Just ooze and bubbles and the feeling of something lurking under there.? Ammi?s horse still pawed and screamed deafeningly in the road outside, and nearly drowned its owner?s faint quaver as he mumbled his formless reflections. ?It come from that stone . . . it growed down thar . . . it got everything livin? . . . it fed itself on ?em, mind and body . . . Thad an? Mernie, Zenas an? Nabby . . . Nahum was the last . . . they all drunk the water . . . it got strong on ?em . . . it come from beyond, whar things ain?t like they be here . . . now it?s goin? home. . . .?
At this point, as the column of unknown colour flared suddenly stronger and began to weave itself into fantastic suggestions of shape which each spectator later described differently, there came from poor tethered Hero such a sound as no man before or since ever heard from a horse. Every person in that low-pitched sitting room stopped his ears, and Ammi turned away from the window in horror and nausea. Words could not convey it?when Ammi looked out again the hapless beast lay huddled inert on the moonlit ground between the splintered shafts of the buggy. That was the last of Hero till they buried him next day. But the present was no time to mourn, for almost at this instant a detective silently called attention to something terrible in the very room with them. In the absence of the lamplight it was clear that a faint phosphorescence had begun to pervade the entire apartment. It glowed on the broad-planked floor and the fragment of rag carpet, and shimmered over the sashes of the small-paned windows. It ran up and down the exposed corner-posts, coruscated about the shelf and mantel, and infected the very doors and furniture. Each minute saw it strengthen, and at last it was very plain that healthy living things must leave that house.
Ammi shewed them the back door and the path up through the fields to the ten-acre pasture. They walked and stumbled as in a dream, and did not dare look back till they were far away on the high ground. They were glad of the path, for they could not have gone the front way, by that well. It was bad enough passing the glowing barn and sheds, and those shining orchard trees with their gnarled, fiendish contours; but thank heaven the branches did their worst twisting high up. The moon went under some very black clouds as they crossed the rustic bridge over Chapman?s Brook, and it was blind groping from there to the open meadows.
When they looked back toward the valley and the distant Gardner place at the bottom they saw a fearsome sight. All the farm was shining with the hideous unknown blend of colour; trees, buildings, and even such grass and herbage as had not been wholly changed to lethal grey brittleness. The boughs were all straining skyward, tipped with tongues of foul flame, and lambent tricklings of the same monstrous fire were creeping about the ridgepoles of the house, barn, and sheds. It was a scene from a vision of Fuseli, and over all the rest reigned that riot of luminous amorphousness, that alien and undimensioned rainbow of cryptic poison from the well?seething, feeling, lapping, reaching, scintillating, straining, and malignly bubbling in its cosmic and unrecognisable chromaticism.
Then without warning the hideous thing shot vertically up toward the sky like a rocket or meteor, leaving behind no trail and disappearing through a round and curiously regular hole in the clouds before any man could gasp or cry out. No watcher can ever forget that sight, and Ammi stared blankly at the stars of Cygnus, Deneb twinkling above the others, where the unknown colour had melted into the Milky Way. But his gaze was the next moment called swiftly to earth by the crackling in the valley. It was just that. Only a wooden ripping and crackling, and not an explosion, as so many others of the party vowed. Yet the outcome was the same, for in one feverish, kaleidoscopic instant there burst up from that doomed and accursed farm a gleamingly eruptive cataclysm of unnatural sparks and substance; blurring the glance of the few who saw it, and sending forth to the zenith a bombarding cloudburst of such coloured and fantastic fragments as our universe must needs disown. Through quickly re-closing vapours they followed the great morbidity that had vanished, and in another second they had vanished too. Behind and below was only a darkness to which the men dared not return, and all about was a mounting wind which seemed to sweep down in black, frore gusts from interstellar space. It shrieked and howled, and lashed the fields and distorted woods in a mad cosmic frenzy, till soon the trembling party realised it would be no use waiting for the moon to shew what was left down there at Nahum?s.
Too awed even to hint theories, the seven shaking men trudged back toward Arkham by the north road. Ammi was worse than his fellows, and begged them to see him inside his own kitchen, instead of keeping straight on to town. He did not wish to cross the nighted, wind-whipped woods alone to his home on the main road. For he had had an added shock that the others were spared, and was crushed forever with a brooding fear he dared not even mention for many years to come. As the rest of the watchers on that tempestuous hill had stolidly set their faces toward the road, Ammi had looked back an instant at the shadowed valley of desolation so lately sheltering his ill-starred friend. And from that stricken, far-away spot he had seen something feebly rise, only to sink down again upon the place from which the great shapeless horror had shot into the sky. It was just a colour?but not any colour of our earth or heavens. And because Ammi recognised that colour, and knew that this last faint remnant must still lurk down there in the well, he has never been quite right since."
