In the decadent sculptures there were signs of thinner vegetation everywhere, and of a decreased country life on the part of the Old Ones. Heating devices were shown in the houses, and winter travelers were represented as muffled in protective fabrics. Then we saw a series of cartouches—the continuous band arrangement being frequently interrupted in these late carvings—depicting a constantly growing migration to the nearest refuges of greater warmth—some fleeing to cities under the sea off the far-away coast, and some clambering down through networks of limestone caverns in the hollow hills to the neighboring black abyss of subterrane waters.
In the end, it seems to have been the neighboring abyss which received the greatest colonization. This was partly due, no doubt, to the traditional sacredness of this special region, but may have been more conclusively determined by the opportunities it gave for continuing the use of the great temples on the honeycombed mountains, and for retaining the vast land city as a place of summer residence and base of communication with various mines.
The linkage of old and new abodes was made more effective by means of several gradings and improvements along the connecting routes, including the chiseling of numerous direct tunnels from the ancient metropolis to the black abyss—sharply down-pointing tunnels whose mouths we carefully drew, according to our most thoughtful estimates, on the guide map we were compiling.
It was obvious that at least two of these tunnels lay within a reasonable exploring distance of where we were—both being on the mountainward edge of the city, one less than a quarter of a mile toward the ancient rivercourse, and the other perhaps twice that distance in the opposite direction.
The abyss, it seems, had shelving shores of dry land at certain places, but the Old Ones built their new city under water—no doubt because of its greater certainty of uniform warmth. The depth of the hidden sea appears to have been very great, so that the earth's internal heat could insure its habitability for an indefinite period.
The beings seem to have had no trouble in adapting themselves to part-time—and eventually, of course, whole-time—residence under water, since they had never allowed their gill systems to atrophy.
There were many sculptures which showed how they had always frequently visited their submarine kinsfolk elsewhere, and how they had habitually bathed on the deep bottom of their great river. The darkness of inner earth could likewise have been no deterrent to a race accustomed to long antarctic nights.
Decadent though their style undoubtedly was, these latest carvings had a truly epic quality where they told of the building of the new city in the cavern sea. The Old Ones had gone about it scientifically—quarrying insoluble rocks from the heart of the honeycombed mountains, and employing expert workers from the nearest submarine city to perform the construction according to the best methods.
These workers brought with them all that was necessary to establish the new venture—Shoggoth tissue from which to breed stone lifters and subsequent beasts of burden for the cavern city, and other protoplasmic matter to mold into phosphorescent organisms for lighting purposes.