For a long time after he was left alone, David Vallory sat on the edge of his bed, buried in thought. With the spy, Backus, at large, it was only a question of time when Lushing would have another weapon in his hands. In odd moments David had made an estimate on the cost of shooting down the menace in the eastern tunnel drifting and concreting the gash which would be left by the blasting out of the fissure material. The figures were appalling. Not only would the profits on the entire contract be likely to disappear in the chasm; there was a chance that there would be a huge loss, as well, since nobody could tell how much of the fissure contents would come down in the blasting. As Eben Grillage had frankly confessed, the line-shortening job had been taken on a narrow margin, and there had been no provision made for untoward happenings. There was but one conclusion to be reached, and by this time David Vallory had passed all the mile-stones of hesitancy. Backus, the worm, must be found and silenced, and there must be no fumbling delay in either half of the undertaking. XXIV No Thoroughfare At the departure of the two fishermen, Virginia Grillage had taken Lucille Vallory under her wing, closing the cottage under the pines and taking the blind girl to the hotel. This left Oswald more or less unattached. Since there was no welcome for him at the foot of the ridge, and David had not even taken the trouble to introduce him to the members of the engineering staff, he spent the greater part of his time at the Inn, devoting himself, so far as Miss Grillage would permit it, to the care and comfort of the helpless one, and taking his meals in due submission at a table with Miss Virginia and her charge, the Englishman, and the heir of profitable breakfast-foods. Beneath these routine time-killings, days in which nothing transpired to break the monotonous round of eating and sleeping and lounging upon the shaded porches of the Inn, Oswald fancied he could feel the tension of an approaching crisis. To a keen-eyed young lawyer whose profession led logically to a study of the human problem in all its phases, the premonitory signs emphasized themselves. Miss Virginia, apparently engrossed in her favorite pastime of playing off one man against another, struck a false note now and then; young Wishart was occasionally jogged out of his customary rut of good-natured indolence; and even the imperturbable Englishman was losing the fine edge of a carefully cultivated Old-World indifference to his surroundings. Notwithstanding these indications, it was Lucille Vallory who first put the impending threat into words, confiding in Oswald one evening when Virginia Grillage had gone for a stroll along the ridge accompanied by her two shadows. “What is it, Herbert?” the blind girl asked; “what is happening to us all?” “What should be happening?” he evaded. “Aren’t you enjoying yourself?”