of the continent of basaltic rocks made by lava floods.

Northern California, northwestern Nevada, and large part of Idaho,
Montana, Oregon, and Washington are included in the basin filled with
lava at the time of the great overflow, which extended far into British
Columbia. It is probable that certain chimneys continued to discharge
until comparatively recent times. Mt. Rainier, Mt. Shasta, and Mt. Hood
are among dead volcanoes.

Quite a different history has the great Deccan lava-field of India,
which covers a larger area than the basin of our Northwest, and is in
places more than a mile in depth. It has no volcanoes, nor signs of any
ever having existed. The floods alone overspread the region, which shows
no puny "follow-up system" of scattered craters, intermittently in
eruption.

THE FIRST LIVING THINGS

Strange days and nights those must have been on the earth when the great
sea was still too hot for living things to exist in it. The land above
the water-line was bare rocks. These were rapidly being crumbled by the
action of the air, which was not the mild, pleasant air we know, but was
full of destructive gases, breathed out through cracks in the thin crust
of the earth from the heated mass below. If you stand on the edge of a
lava lake, like one of those on the islands of the Hawaiian group, the
stifling fumes that rise might make you feel as if you were back at the
beginning of the earth's history, when the solid crust was just a thin
film on an unstable sea of molten rock, and this volcano but one of the
vast number of openings by which the boiling lava and the condensed
gases found their way to the surface. Then the rivers ran black with the
waste of the rocky earth they furrowed, and there was no vegetation to
soften the bleakness of the landscape.

The beginnings of life on the earth are a mystery. Nobody can guess the
riddle. The earliest rocks were subjected to great heat. It is not
possible that life could have existed in the heated ocean or on the
land. Gradually the shores of the seas became filled up with sediment
washed down by the rivers. Layer on layer of this sediment accumulated,
and it was crumpled by pressure, and changed by heat, so that if any
plants or animals had lived along those old shores their remains would
have been utterly destroyed.

Rocks that lie in layers on top of these oldest, fire-scarred
foundations of the earth show the first faint traces of living things.
Lim