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TRACK ILLUMINATER - A flat car covered with a thick layer of sand on which rested an iron brazier filled with blazing pine knots. This was the original headlight used for the first time in 1831 in South Carolina.
TRACTION INCREASER -A mechanism for transfering part of the weight of a fuel car from one of the trucks to the drivinng wheels in order to increase traction in starting. In 1834 E.L.Miller devised a levering mechanism which was used extensivly in Baldwin locomotives until George Escoll Sellers invented an automatic mechanism a few years later.
TRACTION FORCE - The amount of effort exherted by a locomotive in turning its wheels. It is predetermined by a formula involving 5 factors: operating boiling pressure by less 15%, piston area, length of stroke, driving wheel diameter, and weight upon drivers.
TRAILING TRUCK - The truck under the firebox of a locomotive and behind the driving wheels, used to carry part of the engine weight.
TRAIN CAPTAIN - An early-day train conductor.
TRAIN LINES - The brake pipes and brake hoses.
"TRAMWAY" typeAny railway operated by horsepower.
TRAP - A receptacle receiving sand from a sand dome and holding a predetermined amount for each application to the track.
TRIPLE VALVE - A mechanism connected to the brake pipe, the auxiliary reservoir, and the brake cylinder, which regulates the intake, exhaust, and equilization of compressed air in the brake system.
TRIPLEX Type - A Mallet articulated compound locomotive with three driving units, one of which was placed beneath the tender, designed bt George R. Henderson about 1913.
TRUCK - A swiveling wheeled frame carrying a portion of a locomotive or car to guide it in turning sharp curves.
TRUMPET STACK - A chimney shaped like an elongated inverted cone.
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U-V
UNDERCARRIAGE - Early term for a locomotive's frame assembly and running gear.
VALVE - A movable lid covering an opening, the movement of which permits or prevents the passage of steam
VALVE GEAR - A mechanism for directing into and out of the cylinders, by which a locomotive is run backward of foreward.
VALVE ROD - a steel rod which communicates the motion of an eccentric rod to a valve.
VAPOR JACK - A cylinder and piston arrangement used in Ross Winan's Carroll of Carrolton to lift part of the boiler weight from the leading and trailing trucks and apply it to the driving wheels for improved traction at starting and on grades.
VAULCAN COMPOUND Type - A steam locomotive with a high and low pressure cylinder, one above the other, on each side, with interconnecting piston rods stroking a mainrod. It was invented in 1889 by Samual M. Vulcain. See also compound type.
"VIBRATING FRAME" - The name Andrew Eastwick gave to a crude equalizing system applied to his Hercules in 1836. The Driving wheels were mounted on a seperate carriage which teetered up and down to adjust them to the dips and rises. The system functioned effectivly only when the rails rose and fell in unison.
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W-Y
"WAGON-TOP BOILER - A boiler in which the part linking the water section and the firebox was elevated gradually by a conical section to provide maximum height above the crownsheet.
WALKING BEAM - A counter balanced lever.
WALSCHAERTS GEAR - A valve gear performing the same functions as the others, but one of the first to be mounted outside the wheels for convenient servicing. Designed in Belgium in the midnineteenth century, the value of the gear was not recognized until much later.
WARMING SHELF - A shallow shelf above the fire door where tallow for lubricating the sliding valves was kept melted in a long-spouted tin or copper can.
WATER JACKET - An arrangement of outer and inner metal shells surrounding a fire and protected by a curtain of water between them.
WEB - See crank web.
WHEEL BASE - The distance between the points of contact with the rails of the first and last pairs of wheels or, if so noted, between the first pair of locomotive wheels and the last pair of tender wheels.
WHYTE CLASSIFICATION - A system of classifying locomotives by the wheel arrangements, suggested by F. M. Whyte and adopted in the 20th century. An eight wheeled American type, for example, meaning an engine with four guiding wheels, four driving wheels and no trailing wheels.
WRAPPER SHEETS - The outer shell of a firebox, and the metal sheets covering the lagging on a boiler.
WRIST JOINT - A jointproviding flexibility in only one direction, as in the case of a human wrist.
"YELLOWSTONE" Type - A 2-8-8-4 articulated locomotive introduced by the Northern Pacific Railroad in 1929
YOKE - A member that connects tw parts located on opposite sides of a third, which it must straddle.
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9/24/03 3:30:25 PM
