 He wondered how he could ever have thought of planets, even of the Earth, as islands of life and reality floating in a deadly void. Now, with a certainty which never after deserted him, he saw the planets—the ‘earths’ he called them in his thought—as mere holes or gaps in the living heaven—excluded and rejected wastes of heavy matter and murky air, formed not by addition to, but by subtraction from, the surrounding brightness.