Sometimes a bold engineer strikes out into a new method, quicker and less expensive than these piecemeal efforts. Of such was the job at Steubenville, O., where a 205-foot double-track span was erected on heavy falsework alongside the old bridge. In a carefully chosen interval between a service of frequent trains, both the old and the new spans--together weighing 1,300 tons--were fastened together and drawn sideways a distance of twenty-five feet in one minute and forty seconds. The new span was then in place, and the old one--ready to be dismantled--stood on falsework at the side. The entire job had been accomplished in an interval of seventeen minutes between trains. That is not unusual. The floating method is sometimes adopted with remarkable success--especially in the case of draw-bridge spans. There the problem complicates itself exceedingly, for both the water and the land highways must be kept open for traffic; yet it is a matter of record that the Pennsylvania Railroad, operating a fearfully heavy suburban service in and out of Jersey City, recently substituted one draw for another on its Hackensack River Bridge without delaying a single train. * * * * * But even in this high noon of the day of steel, the stone bridge holds its own. The big chiefs of railroad construction look upon it with favor. Higher priced than a steel bridge of equal capacity it requires initial outlay. But forever after, it represents a saving--a saving chiefly in that very important figure, maintenance. A steel bridge requires constant attention and constant expense. A stone bridge requires little of either; and therein lies its strength in its old age. Engineers point to such structures as the Thomas Viaduct down at Relay, or to the wonderful stone bridges that have stood through the centuries in older lands; they bear in mind the constant battle that a steel bridge must make against the ravages of weather and against the sinister thefts of corrosion, and ofttimes they rule in favor of the oldest type of sizable bridge.