d its attraction is so feeble that we should
probably arrive at Mars before it had drawn you back again."

All this was, of course, perfectly self-evident, yet I believe that
but for the warning word of Lord Kelvin, I should have been rash enough
to step out into empty space with sufficient force to have separated
myself hopelessly from the electrical ship.

A Reckless Experiment.

As it was, I took good care to retain a hold upon a projecting portion
of the car. Occasionally cautiously releasing my grip, I experienced for
a few minutes the delicious, indescribable pleasure of being a little
planet swinging through space, with nothing to hold me up and nothing
to interfere with my motion.

Mr. Edison, happening to come upon the deck of the ship at this time,
and seeing what we were about, at once said:

"I must provide against this danger. If I do not, there is a chance that
we shall arrive at Mars with the ships half empty and the crews floating
helplessly around us."

Edison Always Prepared.

Mr. Edison's way of guarding against the danger was by contriving a
little apparatus, modeled after that which was the governing force of the
electrical ships themselves, and which, being enclosed in the air-tight
suits, enabled their wearers to manipulate the electrical charge upon
them in such a way that they could make excursions from the cars into open
space like steam launches from a ship, going and returning at their will.

These little machines being rapidly manufactured, for Mr. Edison had a
miniature laboratory aboard, were distributed about the squadron, and
henceforth we had the pleasure of paying and receiving visits among the
various members of the fleet.

But to return from this digression to our experience of the asteroid. The
latter being a body of some mass was, of course, able to impart to us
a measurable degree of weight. Being five miles in diameter, on the
assumption that its mean density was the same as that of the earth,
the weight of bodies on its surface should have borne the same ratio to
their weight upon the earth that the radius of the asteroid bore to the
radius of the earth; in other words, as 1 to 1,600.

Having made this mental calculation, I knew that my weight, being 150
pounds on the earth, should on this asteroid be an ounce and a half.

Curious to see whether fact would bear out theory, I had myself weighed
with a spring balance. Mr. Edison, Lord Kelvin and the other distingui