When the roadway had been completed to that point, molelike, the engineers and sappers dug into the earth and pushed on. The old roadway, suiting their purposes well, led to the wall at a point nearly midway between two of the watchtowers, which were distant from one another about a mile. Another circumstance which was favorable to the lieutenant's plan was that the neck or isthmus which connected Ruthar to Maeronica was, though high above the sea, comparatively level. Back of a knoll in the forest the miners sank their shaft. Twelve feet down in the earth they struck the living rock and proceeded along that, excavating a tunnel, or gallery, eight feet high by ten feet across. This work was done swiftly, for the tunnel was wide enough so that four men might work in it abreast, and as fast as one quartet was wearied another took its place, and the picks were swinging day and night. As the diggers went on, a multitude of workers behind them carried back the loosened earth and shored the gallery up with timbers so that it might not cave. When Everson returned from the ride to the place of Zoar, he found that his tunnel was ended--against the face of the Kimbrian Wall, which was founded on the rock itself. Following his instructions, the sappers had branched the tunnel right and left along the wall, until the working was in the shape of an elongated letter "T", the cross-arm of which lay along the foundation stones of the wall and was sixty feet long. With the same ceaseless industry that had built the tunnel so swiftly, they then had attacked the face of the wall with chisels and sledges, cutting in at intervals of about ten feet. This had been difficult work and perilous. The rock of the wall was adamant-hard. However, by attacking the cement in which the stones were set, the miners had been able to remove numbers of the great blocks entire, rolling them by dint of herculean effort across the gallery and into cavities made to receive them. In that work had been the danger. Eight men had been crushed under falling fragments--first toll of Ruthar in the warfare. The excavations had been carried into the foundation of the wall a matter of fifteen feet when Everson arrived. He at once ordered that work stopped. Remained only the placing of the explosive. That he superintended in person. Bar by bar--for the lieutenant would suffer no man to carry more than one of old Zenas's patty-cakes at a time--and with extreme care, the melinite was borne in through the tunnel and packed in the cavities in the wall. The geologist's workshop had turned out a plenty of the stuff, and it was used without stint. Everson judged that he placed nearly two tons of the explosive in each of the six chambers under the wall. Banks of loose, dry earth were piled about the melinite charges; Everson laid his wires, and his workmen then filled the cavities with fragments of the rock taken from the wall.