the other.
The cost will be a mere trifle."

"But will the air pass through in that way?"

"Not without help. But we can easily give it help."

"How? Go on. Explain your plan fully."

"Well, we have here three or four of those big fans that the government
had made for the purpose of ventilating the engine rooms and stoke holes
of its ironclads. They utterly failed and were sold as junk. Captain
Hallam bought a lot of them at the price of scrap iron, and sent them
out here. Davidson tried one of them and reported utter failure as a
result. The failure was natural enough, both in the case of the
ironclads and in that of the mine."

"How so?"

"Why, in both cases an attempt was made to force air down into spaces
already filled with an atmosphere denser than that above. That was
absurdly impossible, as any engineer not an idiot should have known."

"And yet you think you can use these fans successfully in ventilating
the mine?"

"I do not think--I know. If Mr. Davidson will permit me to explain----"

"Never mind Davidson. If this experiment is to be tried you shall
yourself be the man to try it. Go on, please."

"But, Duncan, I simply mustn't be known in the matter at all."

"Why not?"

"I have a wife to care for. I can't afford to be discharged. Besides,
the miners like me and they think they have grievances against Davidson.
If he were to discharge me--as he certainly would if I were to appear in
this matter--the whole force would go on strike, no matter how earnestly
I might plead with them not to do so. I don't want that to happen. It
would be an ill return to the company that gave me wages when it was a
question of wages or starvation with me. Worse still, it would mean
poverty and suffering to all the miners and all their helpless wives and
children. No, Duncan, I must not be known in this matter, or have
anything to do with the execution of the plans I suggest. I want you to
treat them as your own; suggest them to Davidson, and persuade him to
carry them out. In that way all of good and nothing of harm will be
done."

"Why, then, haven't you suggested your plans to Davidson?"

"I have, and he has scornfully rejected them. Coming from you he may
treat them with a greater respect."

"Now, before we go any further, Dick--for I like to call you by the old
nickname that alone I knew before our foolish quarrel came to separate
us--before we go any further, let me explain to you that I am absolute
master