Although labour is a vital consideration, it is but one cog in the complex machine by means of which the iron road is driven forward through a new country. Without tools the efforts of the navvy would count for naught, and as time has rolled by inventive effort and engineering skill have contrived more and more wonderful devices to enable the epoch-making work to be fulfilled in the shortest space of time. There is the steam shovel, which will remove two and a half cubic yards of miscellaneous rubble with every swing of its ponderous arm; the grader, whereby the soil is ploughed up and displaced by an endless chain of buckets into capacious wagons for removal; the drag shovel, a huge scoop attached to the end of a chain which is pulled along the ground from a stationary point by steam power, becoming charged with material in its progress, and thus fashioning the cutting; the monitor, whereby tons of gravel are washed down the mountain-side under the disintegrating force of a powerful jet of water similar to a fireman’s hose; and a host of other wonderful implements, all devised for the express purpose of expediting the work in hand. Gunpowder and dynamite are invaluable handmaids, and to-day are used with an astonishing prodigality. Indeed, when the advance is through rock their services are indispensable. Crags, cliffs and even whole hills are blown away bodily by their agency, and the cost often runs into thousands of pounds, miniature volcanoes being produced by the upheavals. [Illustration: A RAILWAY CONSTRUCTION CAMP AMONG THE MOUNTAINS] [Illustration: BUILDING A HIGH BANK ON THE DELAWARE, LACKAWANNA AND WESTERN RAILWAY, U.S.A., BY MODERN METHODS An overhead cableway was stretched across the depression, from which a swinging line was suspended, and on which the trucks were backed to be emptied.]