enly it was falling steadily, gray Earth and its
dark continent now beneath, while with a dwindling rushing roar its
second satellite whirled away above them, passing and vanishing.
Passing as though, to Norman it seemed, all their strange sojourn on
it were passing; the frog-men and their mighty city, Sarja and their
mad flight, the green men and the last terrific battle; all whirling
away--whirling away.

HISTORIC EXPERIMENT PROVES EARTH'S ROTATION

The famous experiment which proves that the "earth do move" by letting
the observer actually see it twisting underneath his feet, an
experiment invented by the French mathematician Jean B. L. Foucault
nearly a century ago was repeated recently under unusually impressive
circumstances before an international scientific congress at Florence,
Italy, the same city where Galileo once was persecuted for holding the
same opinion.

From the center of the dome of the Church of Santa Maria di Fiore,
Father Guido Alfani, director of the Astronomical Observatory,
suspended a 200-pound weight on a wire 150 feet long. On the bottom of
this weight was a tiny projecting point which traced a line on a
table-top sprinkled with sand, as the great pendulum swung slowly back
and forth. At a given signal Father Alfani set the pendulum to
swinging. While the assembled scientists watched it, slowly the line
traced across the sand table-top changed direction.

As Foucault proved long ago and as the watching scientists well knew,
the table was being twisted underneath the pendulum by the rotation of
the earth.

A REVOLUTIONARY AIRPLANE

A new airplane propeller has recently been patented by J. Kalmanson of
Brooklyn, N. Y. Greater speed and marked saving in fuel is claimed for
the invention, which may be attached to any type of airplane.

The device is in two parts, which may be used separately as front and
rear propellers or combined into a single blade. The principle is that
the front one acts to bring air to the other, giving the propeller
more of a hold, so to speak, and greater power. This is accomplished
by four air-spoons, one on each side of each blade of the propeller.

It is said that the device can double the speed of an airplane and
raise it from the ground in ninety feet instead of the 200 feet most
airplanes now require. It is also claimed that the new propeller will
prevent the plane from making a nose drive unless the pilot forces it
to do so, and enable it to make a sa