speed on leaving a station. Observe what a long time it is before it can attain its full velocity. A large part of the total time you require in order to reach the suburbs is consumed in this manner. A hundred years hence trains will almost jump to full speed, somewhat as a motor-car jumps to-day. In collecting passengers at suburban stations, the train, a hundred years hence, will perhaps not stop at all. It will only slacken speed a little; but the platform will begin to move as the train approaches, and will run along beside it, at the same speed as the train itself, so that passengers can get in and out as if the train were standing still. When all are aboard, the doors will be closed all together by the guard, and the platform will reverse its motion, and return to its original position ready for the next train.
With trains travelling at quite 200 miles an hour—and certainly nothing less will satisfy the remoter suburbanites of next century—frightful accidents would occur if precautions were not taken. The moment two trains are in the same section of line they will be automatically cut off from the source of power, and their brakes will at the same time bring them to a standstill. A passenger who put his head out of the window of a train travelling at this speed would be blinded and suffocated; so the windows will be glazed, the oxygenators
