long as there is plenty of it. It all depends on the cost of
extracting the metal. There are scores, yes, hundreds of gold-deposits
well known to-day, which cannot be worked as long as gold stays $20 an
ounce, because it costs almost as much as that to get it out, but
which would be big money-makers if the gold were worth $25.
Three-quarters of the gold-mines of to-day would shut tight like a
clam, if gold were to drop in price even a dollar or two. What a
capitalist wants to-day is ore, and he is not interested in free gold.
What a prospector looks for, is free gold, and he ignores the rock.
I'm telling you all this, now, Jim, because it's what will be the
important thing when we get to talking, later, over your find."

"That's all right," the old prospector answered, "but how can a man
tell when he's tappin' a big lot o' rock or jest a little, if it ain't
the free gold what shows him?"

"He can't tell, as a rule," the mine-owner rejoined. "It takes a
geologist to do that. As I was saying, there are some rules to go by.
Here, I'll give you a notion of how gold came to be in the rocks, and
then you'll see what a geologist can tell and what he can't.

"To start with, you've got to begin 'way at the beginning of things,
before the crust of the earth was solid and when all the rocks of the
crust were in a melted and half-liquid state. So far as we can make
out, the metals seems to have classified themselves at that time, more
or less, according to density. The lighter elements came to the
surface, the heavier ones stayed at the bottom. It wasn't merely a
question of weight, but of gravitation, centrifugal action and a lot
of things I won't stop to explain to you now. Gold, as you know, is
heavy, that is, it possesses extreme density. It stayed therefore,
mainly at the bottom of this semi-molten sea.

"But this sea, which covered the whole of the earth's surface, wasn't
altogether liquid, as the oceans are to-day. It was a seething mass of
different densities, some of it liquid, some of it slimy, some of it
thick like sticky mud, acted upon by fearful whirlwinds of electric
forces such as astronomers see in the sun to-day, and by powerful
internal currents which created vast churning whirlpools of
super-heated matter.

"It's impossible for us to tell where these electric whirlwinds passed
or where these currents were. So, since the original separation of the
metals was highly irregular, no geologist can say with certai