Moreover, if the ray had revealed a cavern of considerable extent he could not expect that it could now pass through it, for the limit of its operations was almost reached.

His electric cumulators would cease to act in a few hours more.

The ray had now descended more than fourteen miles--its limit was fifteen.
Margaret was greatly troubled because of the effect of this result of the light borer upon Roland.

His disappointment was very great, and it showed itself in his face.

His Artesian ray had gone down to a distance greater than had been sometimes estimated as the thickness of the earth's crust, and the result was of no value.