Bromley sprang afoot at the first discharge, but before he could reach the door of the adobe, Ballard came in, carrying a hatful of roughly crumbled brown earth. He was a little short of breath, and his eyes were flashing with excitement. Nevertheless, he was cool enough to stop Bromley's question before it could be set in words.
"It was only one of the colonel's Mexican mine guards trying a little rifle practice in the dark," he explained; and before there could be any comment: "I went out to get this, Gardiner"—indicating the hatful of earth. "It's a sample of some stuff I'd like to have you take back to Boston with you for a scientific analysis. I've got just enough of the prospector's blood in me to make me curious about it."
The geologist examined the brown earth critically; passed a handful of it through his fingers; smelled it; tasted it.
"How much have you got of this?" he asked, with interest palpably aroused.
"Enough," rejoined the Kentuckian, evasively.
"Then your fortune is made, my son. This 'stuff,' as you call it, is the basis of Colonel Craigmile's millions. I hope your vein isn't a part of his."
Again Ballard evaded the implied question. "What do you know about it, Gardiner? Have you ever seen any of it before?"
"I have, indeed. More than that, I have 'proved up' on it, as your Western miners say of their claims. A few evenings ago we were talking of expert analyses—the colonel and young Wingfield and I—up at the house of luxuries, and the colonel ventured to wager that he could stump me; said he could give me a sample of basic material carrying fabulous values, the very name of which I wouldn't be able to tell him after the most exhaustive laboratory tests. Of course, I had to take him up—if only for the honour of the Institute—and the three of us went down to his laboratory. The sample he gave me was some of this brown earth."
"And you analysed it?" inquired Ballard with eagerness unconcealed.
"I did; and won a box of the colonel's high-priced cigars, for which, unhappily, I have no possible use. The sample submitted, like this in your hat, was zirconia; the earth-ore which carries the rare metal zirconium. Don't shame me and your alma mater by saying that this means nothing to you."