the whole thing to the winds. And yet," I
added, regretfully, "I had expected a great deal of personal
gratification from the use of this invention."

"Now listen," said my wife, eagerly; "don't you think it would be
best to do this: use the thing as much as you please for your own
amusement and satisfaction, but let the world wait? It has waited a
long time, and let it wait a little longer. When we are dead let
Herbert have the invention. He will then be old enough to judge for
himself whether it will be better to take advantage of it for his
own profit, or simply to give it to the public for nothing. It would
be cheating him if we were to do the latter, but it would also be
doing him a great wrong if we were, at his age, to load him with
such a heavy responsibility. Besides, if he took it up, you could
not help going into it, too."

I took my wife's advice. I wrote a careful and complete account of
the invention, and, sealing it up, I gave it to my lawyers to be
handed to my son after my death. If he died first, I would make
other arrangements. Then I determined to get all the good and fun
out of the thing that was possible without telling any one anything
about it. Even Herbert, who was away from home, was not to be told
of the invention.

The first thing I did was to buy a strong leathern knapsack, and
inside of this I fastened my little machine, with a screw so
arranged that it could be worked from the outside. Strapping this
firmly to my shoulders, my wife gently turned the screw at the back
until the upward tendency of the knapsack began to lift and sustain
me. When I felt myself so gently supported and upheld that I seemed
to weigh about thirty or forty pounds, I would set out for a walk.
The knapsack did not raise me from the ground, but it gave me a very
buoyant step. It was no labor at all to walk; it was a delight, an
ecstasy. With the strength of a man and the weight of a child, I
gayly strode along. The first day I walked half a dozen miles at a
very brisk pace, and came back without feeling in the least degree
tired. These walks now became one of the greatest joys of my life.
When nobody was looking, I would bound over a fence, sometimes just
touching it with one hand, and sometimes not touching it at all. I
delighted in rough places. I sprang over streams. I jumped and I
ran. I felt like Mercury himself.

I now set about making another machine, so that my wife could
accompany me in my walks; but w