the ordinary electric
current, which was very much more effective. Having made a certain
amount of gold, I disposed of it for a sum which enabled me to buy
improved materials and stronger batteries. In this way I enlarged my
operations until at last I was in a position to build this house and
to have a laboratory where I could carry out my work on a much larger
scale. As I said before, I can now state with all truth that the amount
of my income is only limited by my desires."

"It is wonderful!" gasped Robert. "It is like a fairy tale. But with
this great discovery in your mind you must have been sorely tempted to
confide it to others."

"I thought well over it. I gave it every consideration. It was obvious
to me that if my invention were made public, its immediate result would
be to deprive the present precious metals of all their special value.
Some other substance--amber, we will say, or ivory--would be chosen as a
medium for barter, and gold would be inferior to brass, as being heavier
and yet not so hard. No one would be the better for such a consummation
as that. Now, if I retained my secret, and used it with wisdom, I might
make myself the greatest benefactor to mankind that has ever
lived. Those were the chief reasons, and I trust that they are not
dishonourable ones, which led me to form the resolution, which I have
today for the first time broken."

"But your secret is safe with me," cried Robert. "My lips shall be
sealed until I have your permission to speak."

"If I had not known that I could trust you I should have withheld it
from your knowledge. And now, my dear Robert, theory is very weak work,
and practice is infinitely more interesting. I have given you more than
enough of the first. If you will be good enough to accompany me to the
laboratory I shall give you a little of the latter."

CHAPTER XI. A CHEMICAL DEMONSTRATION.

Raffles Haw led the way through the front door, and crossing over the
gravelled drive pushed open the outer door of the laboratory--the same
through which the McIntyres had seen the packages conveyed from the
waggon. On passing through it Robert found that they were not really
within the building, but merely in a large bare ante-chamber, around
the walls of which were stacked the very objects which had aroused his
curiosity and his father's speculations. All mystery had gone from
them now, however, for while some were still wrapped in their sackcloth
coverings, other