friction with the planet's atmosphere, or else be smashed to atoms by
the shock?"

_I_. "We might steer by the stars to a point on the planet's orbit,
mathematically fixed in advance, and wait there until it comes up. The
atmosphere of the approaching planet would act as a kind of buffer, and
the fall of the car could be further checked by our means of recoil, and
also by a large parachute. We should probably be able to descend quite
slowly to the surface in this way without damage; but in case of peril,
we could have small parachutes in readiness as life-buoys, and leap from
the car when it was nearing the ground."

_G_. "I presume you are taking into account the velocity of the planet
in its orbit? That of the earth is 18 miles a second, or a hundred times
faster than a rifle bullet; that of Venus, which is nearer the sun, is a
few miles more; and that of Mars, which is further from the sun, is
rather less."

_I_. "For that reason the more distant planets would be preferable to
land on. Uranus, for instance, has an orbital velocity of four miles a
second, and his gravity is about three-fourths that of the earth.
Moreover, his axis lies almost exactly on the plane of the ecliptic, so
that we could choose a waiting place on his orbit where the line of his
axis lay in the direction of his motion, and simply descend on one of
his poles, at which the stationary atmosphere would not whirl the car,
and where we might also profit by an ascending current of air. The
attraction of the sun is so slight at the distance of Uranus, that a
stone flung out of the car would have no perceptible motion, as it
would only fall towards the sun a mere fraction of an inch per second,
or some 355 feet an hour; hence, as Dr. Preston has calculated, one