In no other part of the canal work do these cost-keeping reports tell such a graphic story as in Culebra Cut. In spite of the fact that as the cut became deeper it became narrower, and the slides and breaks became more troublesome, to say nothing of the extra effort required to get the excavated material out of the cut, every unit cost was forced down notch by notch and year by year until the bottom in costs was reached only a little before the actual bottom of the cut was exposed to view. For instance, in 1908 it cost 11-1/2 cents a yard to load material with steam shovels, while in 1912 it cost less than 7 cents. In 1908 it cost more than 14 cents a yard for drilling and blasting; in 1912 it cost less than 12 cents. In 1908 it cost $18.54 to haul away a hundred yards of spoil; in 1912 it required only $13.31 to perform the same operation, although the average distance it had to be hauled had increased 50 per cent. In 1908 it cost more than 13 cents a yard to dump the material as compared with less than 5 cents in 1912. The whole operation of excavating and removing the material, including overhead charges and depreciation, fell from $1.03 a cubic yard in 1908 to less than 55 cents a yard in 1912. And that is why 232,000,000 cubic yards of material were removed for less than it was estimated 135,000,000 cubic yards would cost. To remove the 105,000,000 cubic yards of earth from the backbone of the Americas required about 6,000,000 pounds of high-grade dynamite each year to break up the material, so that it might be successfully attacked by the steam shovels. To prepare the holes for placing the explosives required the services of 150 well drills, 230 tripod rock drills, and a large corps of hand drillers. Altogether they drilled nearly a thousand miles of holes annually. During every working day in the year about 600 holes were fired. They had an average depth of about 19 feet. In addition to this a hundred toe holes were fired each day, and as many more "dobe" blasts placed on top of large boulders to break them up into loadable sizes. So carefully was the dynamite handled that during a period of three years, in which time some 19,000,000 pounds were exploded in Culebra Cut, only eight men were killed. [Illustration: STEAM SHOVELS MEETING AT BOTTOM OF CULEBRA CUT L. K. ROURKE] [Illustration: THE MAN-MADE CANYON AT CULEBRA]