III. Luminous gases surround the nucleus.
IV. The drift-clays are the result of the grinding
up of granitic rocks.
V. No such deposits, of anything like equal magnitude,
could have been formed on the earth.
[1. “The Great Ice Age,” p. 13.]
{p. 81}
VI. No such clays are now being formed under
glaciers or Arctic ice-sheets.
VII. These clays were ground out of the substance
of the comet by the endless changes of position of
the material of which it is composed as it flew through
space, during its incalculable journeys in the long
reaches of time.
VIII. The earth-supplies of gravel are inadequate
to account for the gravel of the drift-deposits.
IX. Neither sea-beach nor rivers produce stones
like those found in the Drift.
I pass now to the next question.
{p. 82}
COULD A COMET STRIKE
THE EARTH?
READER, the evidence I am about to present will satisfy
you, not only that a comet might have struck the earth
in the remote past, but, that the marvel is that the
earth escapes collision for a single century, I had
almost said for a single year.
How many comets do you suppose there are within the
limits of the solar system (and remember that the
solar system occupies but an insignificant portion
of universal space)?
Half a dozen-fifty-a hundred-you will answer.
Let us put the astronomers on the witness-stand:
Kepler affirmed that “COMETS ARE SCATTERED THROUGH
THE HEAVENS WITH
AS MUCH PROFUSION AS FISHES IN THE OCEAN.”
Think of that!
“Three or four telescopic comets are now entered
upon astronomical records every year. Lalande
had a list of seven hundred comets that had been observed
in his time.”
Arago estimated that the comets belonging to the solar
system, within the orbit of Neptune, numbered seventeen
million five hundred thousand!
Lambert regards five hundred millions as a
very moderate estimate![1]
[1. Guillemin, “The Heavens,” p.
251.]
{p. 83}
And this does not include the monstrous fiery wanderers
who may come to visit us, bringing their relations
###
ORBITS OF THE PERIODIC
COMETS.
along, from outside the solar system—a
sort of celestial immigrants whom no anti-Chinese
legislation can keep away.
Says Guillemin:
“Leaving mere re-appearances out of the question,
new comets are constantly found to arrive from
the depths of space, describing around the sun
orbits which testify to the attractive power of that
radiant body; and, for the
{p. 84}
most part, going away for centuries, to return again
from afar after their immense revolutions."[1]
But do these comets come anywhere near the orbit of
the earth?
