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Operation of a Steam Locomotive

Every steam locomotive, from the smallest to the largest one, required a machinist and a stoker (or fireman). Albeit the machinist is who "directed the game", the stoker immediately followed him in the railway hierarchy, and his function was one of vital importance for he was the responsible of delivering the steam required for the proper functioning of the train. With the eyes on the manometer and the water level, he regulated the injectors of the tender, ensuring that the boiler were always full. Promptly, keeping his balance on the rickety footbridge, he opened the fire door and spread upon the grill a layer of coal, checking if the smoke exhausted through the stack was as black and thick as it should be. Firstly two shovels of coal on the bottom corners, then one more in the center of the grill and finally another two next to the fire door. And so, without stop, more than one tonne of coal every hour!

Note: during a travel, the water was stored in the tender with the help of a "spoon" submerged in a canal running between the rails, and when stopping at a station by means of a bridge crane. In such case, the machinist usually controlled the crane while the stoker watched the filling of the deposit.

Operation of a steam locomotive

Like the machinist, the stoker had to know every meter of the railway, for each ascension in the route demanded an increase in power, and each descent meant some shovels of coal less and the possible obtention of the economy bonus which was granted to a driving team. When running inside a tunnel or entering a station at low speed there existed the danger of a return in the flames. Indeed, a rear air stream entering abruptly upon the smoke box and the boiling tubes could set fire on the cabin if the stoker had left the fire door open by mistake. Inside the cabin it was impossible to sustain a conversation, not only because of the steam whistles and the smoke, but also because of the strong crunches from the footbridge and the deafening hammering caused by the driving wheels. Still, both men could understand each other without any word, for their daily coexistence habituated the one to the other in an almost total way.

Note: steam locomotives were fitted as well with a "black box" which registered in a graphical chart the different speeds reached on each railway section. Besides, in every railroad switch and signaling point an electrical system triggered a signal which had to be stopped by the machinist or the stoker. With these measures, the inspectors obtained a complete registry of each travel.

In a railway company, a youngster hired at the age of fourteen remained several years working in the deposit as an apprentice. There he familiarized himself with the locomotives, scraped the slags on the grills, cleaned the soot on the stacks, learned to keep the pressure and carefully burnished the copper parts on the wagons so they could shine under the sun in their next travel. A certain day, he would be ordered to accompany in the cabin a veteran machinist and, with a shovel in hands, he would learn the craft of being a stoker. He would require several years of hard work before being promoted as machinist, as long as he knew by heart every regulation about railway driving. The machinist was entitled only to manage the control instruments on the locomotive: the regulator, the valve and the brake.

Operation of a steam locomotive

When the station master gave the departure signal by means of a whistle, the machinist looked at the water level, the two manometers which indicated the pressure on the boiler and the dome, from which the steam passed to the cylinders. Then he opened the valve to allow the steam to push the pistons in the direction for forward march. He released the brakes and softly actuated the regulator; and with a smoke puff and a steam whistle, the express train pulled along the rails by its driving wheels and started to move. To start smoothly, the machinist had to know very well the traction power of his machine, as well as the total weight of the convoy which it towed, for if he sent insufficient steam through the regulator there would not be enough power to move the train, and if otherwise he sent too much steam the wheels would slip on the rails, rotating without advancing. When the rails were on a slope or were slippery due to the rain, it would be necessary to release some sand between the driving wheels and the rails, by means of an injector, to increase adherence between them.

Once the train left the station, it crossed the deposit towards the main railroad, where the machinist, managing the regulator and the valves, accelerated more and more. Finally, when reaching cruise speed, the steam admission was reduced until the piston did not perform more than a 35 percent of its stroke, to capitalize to the maximum its expansion force. But moving the train was not everything; it was also necessary to see on the distance the speed panels and the signals on the border of the railroad. Looking through the window on the cabin, with a hand on the regulator, prepared to reduce speed when approaching a curve, a bridge or a station, or to stop if seeing a red light in the signaling gate, the machinist had, above all, to make sure that the braking system had enough pressure and was apt to work properly, because for completely stopping a convoy a stretch of more than 1000 meters could be required.

Note: American locomotives were equipped with a bell that the machinist rang on every level crossing.

Bell of a steam locomotive

The braking system by means of compressed air, created by the American engineer Westinghouse, and the vacuum brake developed in Great Britain shared the European market. The railway companies equipped their locomotives with either system, so the wagon manufacturers had to provide these with both systems. So, the Orient Express, which frequently changed machines along its long route, crossed through three countries while using the air-compressed system and through another three while using the vacuum system.

Out of the two systems, the first was the simplest one. In the locomotive were installed a steam compressor and a main air tank, connected by a main duct to other auxiliary tanks placed in the rear part of every wagon, and which had a triple valve. The machinist reduced the pressure in the circuit by actuating in the braking lever; then the triple valve opened pass to the braking cylinders and the compressed air from the auxiliary tanks pushed the pistons which pressed the brake shoes of every wheel. This system allowed to perform a gentle braking in each wagon. Besides, if a wagon eventually detached from the convoy or if the reviser actuated the alarm ring, the pressure on the circuit fell instantly and the train stopped automatically. To this infallible mechanism is due an important reduction in the number of accidents. Later, with the advent of light-steel wagons, drum brakes were adopted similar to those used in automobiles.

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