Underground

It was a daring ruse that had taken Ned Winston down the shaft of the
"Independence" mine with the midnight shift. Not even the professional
enthusiasm of a young engineer could serve to justify so vast a risk,
but somehow this battle of right and wrong had become a personal
struggle between himself and Farnham; he felt, without understanding
clearly why, that the real stake involved was well worth the venture,
and would prove in the end of infinitely more value to him than any
settlement of the mere mining claims at issue. For several hours he
had been below in the tunnel of the "Little Yankee," measuring
distances, and sampling the grade of ore. All the afternoon and much
of the early night had been utilized in a careful exploration of the
surface ledges; creeping in, under protection of the low-growing
cedars, as closely as a vigilant rifle-guard would permit, to the great
ore dump of the busy "Independence"; diligently studying their system
of labor, and slowly crystallizing into shape his later plan of action.

He was already morally convinced that the Farnham people were actively
engaged in stealing the "Little Yankee" ore; that they were running
their tunnel along the lead of the latter; that they were doing this
systematically, and fully conscious of the danger of discovery. His
lines of survey, the nature of the ore bodies, the muffled sound of
picks, plainly discernible in the silent breast of the "Little Yankee"
while he lay listening with ear to the rock, as well as the close
secrecy, all combined to convince him fully of the fact. Yet such
vague suspicions were perfectly useless. He must have absolute,
convincing proof, and such proof could be obtained nowhere excepting at
the bottom of the "Independence" shaft.