At last a mighty metropolis rose on the bottom of that Stygian sea, its architecture much like that of the city above, and its workmanship displaying relatively little decadence because of the precise mathematical element inherent in building operations.
The newly bred Shoggoths grew to enormous size and singular intelligence, and were represented as taking and executing orders with marvelous quickness. They seemed to converse with the Old Ones by mimicking their voices—a sort of musical piping over a wide range, if poor Lake's dissection had indicated aright—and to work more from spoken commands than from hypnotic suggestions as in earlier times.
They were, however, kept in admirable control. The phosphorescent organisms supplied light with vast effectiveness, and doubtless atoned for the loss of the familiar polar auroras of the outer-world night.
Art and decoration were pursued, though, of course, with a certain decadence. The Old Ones seemed to realize this falling off themselves, and in many cases anticipated the policy of Constantine the Great by transplanting especially fine blocks of ancient carving from their land city, just as the emperor, in a similar age of decline, stripped Greece and Asia of their finest art to give his new Byzantine capital greater splendors than its own people could create. That the transfer of sculptured blocks had not been more extensive, was doubtless owing to the fact that the land city was not at first wholly abandoned.
By the time total abandonment did occur—and it surely must have occurred before the polar Pleistocene was far advanced—the Old Ones had perhaps become satisfied with their decadent art—or had ceased to recognize the superior merit of the older carvings. At any rate, the æon-silent ruins around us had certainly undergone no wholesale sculptural denudation, though all the best separate statues, like other movables, had been taken away.
The decadent cartouches and dados telling this story were, as I have said, the latest we could find in our limited search. They left us with a picture of the Old Ones shuttling back and forth betwixt the land city in summer and the sea-cavern city in winter, and sometimes trading with the sea-bottom cities off the antarctic coast.
By this time the ultimate doom of the land city must have been recognized, for the sculptures showed many signs of the cold's malign encroachments. Vegetation was declining, and the terrible snows of the winter no longer melted completely even in midsummer.
The saurian live stock were nearly all dead, and the mammals were standing it none too well. To keep on with the work of the upper world it had become necessary to adapt some of the amorphous and curiously cold-resistant Shoggoths to land life—a thing the Old Ones had formerly been reluctant to do. The great river was now lifeless, and the upper sea had lost most of its denizens except the seals and whales. All the birds had flown away, save only the great, grotesque penguins.
What had happened afterward we could only guess. How long had the new sea-cavern city survived? Was it still down there, a stony corpse in eternal blackness? Had the subterranean waters frozen at last? To what fate had the ocean-bottom cities of the outer world been delivered? Had any of the Old Ones shifted north ahead of the creeping ice cap? Existing geology shows no trace of their presence. Had the frightful Mi-Go been still a menace in the outer land world of the north? Could one be sure of what might or might not linger, even to this day, in the lightless and unplumbed abysses of earth's deepest water?