Book Two Beyond the Great Oblivion Chapter 9 Planning the Great Migration

Stern rigged a tripod for the powerful field-glasses he had rescued from the Metropolitan Building, and by an ingenious addition of a wooden tube and another lens carefully ground out of rock crystal, succeeded in producing (on the right-hand barrel of the binoculars) a telescope of reasonably high power. With this, of an evening, he often made long observations, after which he would spend hours figuring all over many sheets of the birch bark, which he then carefully saved and bound up with leather strings for future reference.

In Van's set of encyclopedias he found a fairly large celestial map and thorough astronomic data. The results of his computations were of vital interest to him.

He said to Beatrice one evening: "Do you know, that wandering black patch in the sky moves in a regular orbit of its own? It's a solid body, dark, irregular in outline, and certainly not over five hundred miles above the surface of the earth."

"What can it be, dear?"

"I don't know yet. It puzzles me tremendously. Now, if it would only appear in the daytime once in a while, we might be able to get some information or knowledge about it; but, coming only at night, all it records itself as is just a black, moving thing. I'm working on the size of it now, making some careful studies. In a while I shall probably know its area and mass and density. But what it is I cannot say--not yet."