cooling down, new chemical compounds, and probably elements would be
formed, since the so-called elements are perhaps mere combinations of a
primordial substance which have been produced at various temperatures.
The heavier elements, such as platinum, gold, and iron, would sink
towards the core; and the lighter, such as carbon, silicon, oxygen,
nitrogen, and hydrogen, would rise towards the surface. A crust would
form, and portions of it breaking in or bursting out together with
eruptions and floods of molten lava, would disturb the poise of the
planet, and give rise to inequalities of surface, to continents, and
mountains. When the crust was sufficiently stable, sound, and cool, the
mists and clouds would condense into rivers, lakes, or seas, and the
atmosphere would become clear. In due course life would make its
appearance."

"Can you account for that mystery?"

"No. Science is bound in honour, no doubt, to explain all it can without
calling in a special act of creation; but the origin of life and
intelligence seems to go beyond it, so far. Spontaneous generation from
dead matter is ruled out of court at present. We believe that life only
proceeds from life. As for the hypothesis that meteoric stones, the
'moss-grown fragments of another world' may have brought life to the
earth, I hardly know what to think of it."

"Has life ever been found on a meteoric stone?"

"Not that I know. Carbon, at all events in the state of graphite and
diamond, has been got from them. They arc generally a kind of slag,
containing nodules or crystals of iron, nickle, and other metals, and
look to me as if they had solidified from a liquid or vapour. Are they