A Dynamometer Car.

Attached to the Royal Scot, the express locomotive which accomplishes the London to Carlisle run of 299 1/2 miles in 5hr. 38m., is a dynamometer car in which is an instrument that tells the speed, drawbar pull, and the distance run of the train. The speed is calculated to a second. Sixty miles per hour is regarded as a good pace even for an express, but the dynamometer shows that speeds round about seventy miles are frequently attained. Sometimes seventy-five miles is reached, although the train is run strictly to schedule.

The maximum horse-power of the Royal Scot on a normal journey is 1100. One can tell by looking at the instrument which records the horse-power that is being exerted, whether the train is climbing, on the level, or descending. This train, excluding the engine, weighs about 449 1/2 tons, and consists of sixteen coaches. The engine consumes about 11,6331b. of coal and 9600 gallons of water on each journey.