These, with very few exceptions, had risen from the ranks. They knew how to do everything from driving a spike to running an engine. They had been drilled in that best of all schools, the school of experience. The superintendents knew their divisions, every foot of track, every siding, every fill, bridge, and crossing, more thoroughly than the ordinary man knows the walk from his front door to the gate. They had gone over the road so often, had studied it so thoroughly, that they had developed a sort of special sense in regard to it. Put them down anywhere along it, blindfolded, on the darkest night, and, at the end of a moment, they could tell where they were. They knew each target by its peculiar rattle as the train sped past. They knew the position of every house--almost of every tree and rock--along it. They knew the pitch of every grade, the degree of every curve; they knew the weak spots, and laboured ceaselessly to strengthen them. Now, as the special swept westward from general headquarters, superintendent after superintendent clambered aboard, as his division was reached, and pointed out to the president and other general officers the weak spots along it. He showed where the sidings were insufficient, where the grade was too steep to be passed by heavy trains, where a curve was too sharp to be taken at full speed without danger, where a bridge needed strengthening or replacing by a masonry culvert. He pointed out stations which were antiquated or inadequate to the growing business of the road, and suggested changes in schedule which would make for the convenience of the road's patrons. For a railroad is like a chain--it is only as strong as its weakest link, and the tonnage which an engine can handle must be computed, not with reference to the level track, but with reference to the stiffest grade which it will have to pass before reaching its destination--except, of course, in cases where the grade is so stiff, as sometimes happens on a mountain division, that it becomes a matter of economy to keep an extra engine stationed there to help the trains over, rather than trim the trains down to a point where a single engine can handle them. The president listened to the arguments and persuasive eloquence of his superintendents, and nodded from time to time. His stenographer, sitting at his elbow, took down the recommendations and the reasons for them, word for word, as well as a comment from the president now and then. As soon as general headquarters were reached again, all this would be transcribed, typewritten copies made and distributed among the general officers; the recommendations would then be carefully investigated and approved or disapproved as might be.