"The chances are," said he, "that, when we do strike it at the lower level, the wash itself will be deeper and wider."
This thought was a wonderful incentive to them all, for the gold-carrying gravel laid bare in the other workings was scarcely two feet in thickness, and, though its richness was unquestionable, its limited nature was only too apparent. Bob and Jack took their turns in the shaft with great good humour and enthusiasm, and though at first their efforts to penetrate the flinty formations encountered were almost unavailing, they quickly acquired the science of the work under the constant guidance of Mackay, who also taught them how to temper their tools for the different kinds of strata, how to drill holes for the gelignite charges so as to obtain the most efficient results. Their early training especially fitted them for this kind of tuition, and they proved very apt pupils. Mackay, though such a strong man himself, was no advocate of the supremacy of muscle even in shaft-sinking.
"Science beats it every time," said he. "Of course, I'm no denyin' that, where baith strength and science are combined there's a wonderfu' advantage, but it doesna often happen that a strong man physically is blessed wi' a superabundity o' mental gifts——"
Jack, of course, could not resist the interruption. "We can't allow that from you, sir," in his most sedate tones.
Mackay smiled. "I'm vera pleased to have your implied testimonial, Jack," he returned, with twinkling eyes; "but then I was aboot to remark that an exception was needed to prove any rule, an' I was to assume mysel' to be the exception in this case. No, no, mind conquers matter, and that is why you two are just as fitted to pit doon a shaft as the strongest navvy in the country." All of which the boys found to be quite in accordance with facts when they got accustomed to wielding the pick, hammer, and drill.
"Observe any cracks in the formation," their kindly instructor would call down to them; "attack everything in the lines o' least resistance." And by following his advice to the letter they quickly discovered that gold-mining was by no means as difficult as they had imagined.
Now, just when the first week of their labours had concluded, the shaft was sunk twenty feet; a few more feet would decide whether or not Bob's theory would prove correct.
"I tell you what, mates," said Nuggety Dick that evening, "you were just a bit venturesome in sinking so far from the main workings."
"I don't think so," returned Bob, confidently. "We'll get there all right, Nuggety. Another five feet should do it." And another five feet did do it. Two days later Mackay's pick broke through the covering layer of diorite in the bottom of the shaft, and with a grunt of satisfaction he called on Jack, who was at the windlass, to lower the bucket.