of the entire train; a resistance including all the internal resistances of the engine, the resistance of the curves, easy although they were, and the loss in accelerating and retarding the train in starting and stopping. This estimate of resistance would correspond, at the observed speed of 5 miles an hour (upwards of ¾ of an hour having been consumed on the 4 miles), to 185 indicated H.P., which, with the driving wheels, making but 28 revolutions per minute, would be the utmost that an engine with but 1,038 square feet of heating surface could be expected to exert. This was the highest result observed during the three weeks' trial, but one or two others are worthy of mention. On the Delaware division of the same line, the train, of 1,572 tuns' weight, was run over 5 consecutive miles of absolutely level line, at a mean rate of 9.23 miles an hour, and during the same day, over 5 other consecutive miles of level at a mean rate of 9.7 miles per hour. On both levels there were 14½ chain curves of good length, and the speed, from 9 to 12 miles an hour, at which the train entered the respective levels, was not quite regularly maintained throughout the half hour expended in running over them. But if even 7 lbs. per tun of the total weight be taken as the resistance at these speeds, the tractive force will be 11,004 lbs., which is more than one fourth the adhesion weight of 40,050 lbs. On the next day, the same engine drew 30 wagons weighing 466½ tuns, or, including engine and tender, 514 tuns nearly, up a gradient of 1 in 117½, three miles long, at a mean speed of 10¼ miles an hour. The resistance due to gravity was 9,814 lbs., and supposing the other resistance to traction to amount to no more than 7 lbs. per tun, the total resistance would be 13,412 lbs., corresponding to a mean effective cylinder pressure of 117 lbs. per square inch, and to a co-efficient of adhesion of almost exactly one third.