RAILROAD DICTIONARY

BACKHEAD - The back end of the boiler, in which the fire door is placed.

BACK PRESSURE - The pressure remaining when a piston exhausts steam, against which the steam taken in must work.

BALANCED COMPOUND TYPE - A steam locomotive with two high-and two- low pressure cylinders. Developed in France in the 1870s, its smooth action made itpopular in Europe. In the United States, Samuel M.Vauclain and Francis J.Cole, each developed versions of the engine, but high maintenance costs outweighed their fuel economy.

BALLAST - Broken stone or gravel placed in a roadbed to provide a sturdy surface for the track and to facilitate drainage.

"BALLAST-SCORCHER" - A fast driving engineer.

BALLOON STACK - A chimney resembling the man carrying baloons of the 19th century. The lower section was shaped like an inverted cone, and the one above it was cylindrical, topped either by a shallow dome formed of wire screening or by a third section tapering inward again and similarly capped with sreening. Note: See More in the IH-Series.

"BARREL" - Common railroad parlance for a boiler.

BEARER - Any small wheel either on a truck or attached directly to a locomotive frame, which supports weight but to which power is not supplied.

BEARING - A load-carrying part upon which an axle or pivot turns or moves.

BEARING BLOCK - A small part bored to receive an axle or a pivot.

"BERKSHIRE" TYPE - A 2-8-4 locomotive introduced by Lima Locomotive Works in 1925. The name was derived from its early use by the Boston & Albany in the Berkshire Hills

"BICYCLE" TYPE - A 4-2-2 locomotive produced by the Baldwin Works in 1880.

"BIG BOY" - Any one of a fleet of Union Pacific 4-8-8-4 articulated locomotives built by the American Locmotive Company between 1941 and 1944. The largest conventional steam locomotives ever built, they weighed 604 1/2 tons and exerted a traction effort of 135,375 pounds.

"BIG-HOLING THE WESTINGHOUSE" - In an emergency, uncovering all the openings in the control valve of an airbrake system at the same time, thus applying its full force.

BLENKINSOP RACK - See rack rail. (when I get to "R")

BLIND TIRE - A ring of iron or steel, encompassing a driving wheel center, that has no flange. This permits it to adjust itself to rail curvatures without binding.

"BLOOMER" TYPE - A 2-2-2 high wheeler designed in England in the midnineteenth century. Its name derived from the fact that there were no framing members or rods outside the driving wheels, leaving them exposed as the legs of the feminist in the briefs introduced by Amelia Bloomer.

BOILER - A metal container in which water is converted to steam by the heat of the fire box.

BOLSTER - A wooden or steel beam placed across the frame of a truckto receive the weight of the engine.

"BOOMER" - A 19th & early 20th century term for a railroad worker who drifted from job to job.

BORE - The inner diameter of a cylinder, or, loosly, the cylinder cavity.

BRAKE CYLINDER - An iron cylinder containing a piston operated by compressed air to apply the air brakes.

BRAKE HOSE - A flexible tube which connects the brake pipes between cars.

BRAKE PIPE - An iron pipe connecting the engineer's brake valve with the air brake apparatus on the cars behind.

BRICK ARCH - A sloping baffle made of firebrick, placed in a furnace to provide more time for embers to burn before they reach the flues. George S.Griggs applied brick arches to locomotive furnaces as early as 1857, but the did no achieve popularity until 1900.

BRIDGE WALL - A water filled partition partially separating a forward extension of the furnace from the coal burning section.

BROAD-GUAGE LINE - A track wider than the standard guage of 4 feet 8 1/2 inches.

BUMP - To replace or demote.

BURY FIREBOX - A furnace with a hemispheric top, invented by the English designer Edward Bury in the early 1830s. Structuarlly strong, it was popular until increasinly large locomotives required fireboxes with larger grate areas.
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C

CAB - A shelter on the locomotive for the enginemen,usually at the back end of the boiler. Cabs came into being about 1843.

"CABBAGE CUTTER" - A freight hauler, so called because it main and side rods swept close to the ground at the lowest points in their long strokes.

CABBAGE HEAD STACK - A chimney with a bulbous top that served as a repository for wood ashes.

"CAMELBACK" or "MOTHER HUBBARD" TYPE - A locomotive with the cab on top of the boiler. The term should not be confused with "Camel," which referred to much earlier engines designed by Ross Winans

"CAMEL" TYPE - An 0-8-0 engine developed by Ross Winans in the 1840s, which gave the appearance of a dromedary with a rider on its back, because of the placement of the steam dome and the engineer's controls in front of the furnace. The term was also applied tothe Baltimore & Ohio's first ten-wheelers.

CHAIR - A clamp of iron or steel, that supports a rail.

"CHALLENGER" TYPE - A high speed 4-6-6-4 articulated locomotive, eaually competent in freight and passenger service.

"CHEESE" BOILER - Developed by Phineas Davis for his York, this upright boiler consisted of a water jacket surrounding a central furnace, and a shallow drum suspended above the grates. The drum when viewed through the fire door, was thought to resemble a cheese, thus giving the entire assembly its name.

"CHESAPEAKE" TYPE - A 2-8-8-2 simple articulated locomotive first used by yhe Chesapeake & Ohio Railway after world war 1. It was soon adopted by practically every railroad confronted by stiff grades and heavy traffic.

CHILLED RIM - The periphery of a cast iron wheel toughened by a process introduced by Ross Winans in the 1830s, using an iron mold rather than one made of sand. When the molten iron contacted the mold, it solidified almost at once, producing treads and flanges of extremely hard and wear-resisting crystalline texture.

"THE CITY OF IRON HORSES" - Paterson, New Jersey, so called because no other city matched its locomotive output in the last half of the 19th century. Before 1900, more than 10,000 of the 60,000 engines built in the United States were manufactured there.

"CLOCK" - A circular steam guage mounted on the backhead of the boiler, first used in the late 1850s.

"COLUMBIA" TYPE - A 2-4-2 locomotive. The first engine of this type was produced by the Baldwin Works in 1892.

COMBUSTION CHAMBER - A spce in a boiler where combustion is promoted and additional heat obtained from gasses before they enter the fire tubes. The combustion cheamber theory was originally produced by Isaac Dripps in the 1830s with the Monster, but not made practical untill 100 years later.

COMPOUND TYPE - A steam locomotive using steam released from one cylinder in a second cyclinder.

CONNECTING ROD -See mainrod (When I get there)

"CONSOLIDATION" TYPE - A locomotive of the 2-8-0 wheel arrangement, built primarily for freight service. The first engine of this type was designed in 1866 by Alexander Mitchell of the Lehigh Valley Railroad.

"CRAMPTON" TYPE - A locomotive with a single pair of driving wheels from 7 to 8 feet in diameter, developped in England in the mid 19th century. Although these engine were very fast, inadequate weight weight on the drivers gave them poor traction. The John Stephens, designed by Isaac Drippe in 1847, was the first American version of this type.

CRANK - A device attached to a shaft, one end of which is free to rotate about the shaft's axis, used to convert rotary to reciprocating motion or vice versa.

CRANK DISK -See crank web.

CRANKED AXEL - A driving axel provided with cranks inside the wheels mounted upon it to which the mainrods transmit motion.

CRANK PIN - A short cylindrical piece attached it a crank on a driving wheel or adjoining to the two disks, or webs, of a crank axel. It transmits the reciprocating motion of the piston to the driving wheel.

CRANK WEB - One of two flat steel pieces of circular or other shape attacheded to the driving axel, between which is the crank pin. (we got here fast enough.)

CROSS-COMPOUND TYPE - A steam locomotive witha hihg-pressure cylinder on one side and a low pressure one on the other, the second cylinder using the steam exhausted by the first. The cross-compound was introduced in 1887 by A.von Borries of Germany and T.W.Worsdell of England.

CROSS-STRINGER - A transverse beam bolted to the longitudinal stringers forming the underlayment for the plates or strap iron rails of early track. Cross-stringers held the longitudinal members in parallel alignment.

CROSSTIE - A wooden beam laid at right angles to and beneath rails for support. In the 1830s wooden crossties were used by Robert L.Stevens as a stop gap measure until more stone could be quarried for the Camden & Amboy Railroad track then being laid across New Jersey. The wooden ties were found to have grater resiliency and thus permit higher operating speeds.

CROWNSHEET - The roof of a firebox.

CULM The screenings of refuse coal.

CUP WHISTLE - A small locomotive whistle employing steam. Popular in England in the 1830s, it was fist used in America on a 4-2-0 constucted by Thomas Rogers in 1837. The idea for the whistle originated in a Welsh iron foundry, where one had been devised to signal the beginning and end of a working day.

CYLINDER - A chamber with circular ends and parallel sides through which a piston is driven.

CYLINDER HEAD - A metal cover on the end of a cylinder
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D

"DEADHEAD" - A locomotive hauled by another.

"DECAPOD" TYPE - 2-10-0 freight locomotive introduced in 1867 by a Lehigh Valley master mechanic Alexander Mitchell.

DIESEL ENGINE - An internal combustion engine using compressed air to ignite fuel injected into the cylinder, where a piston is actuated by the combustion and expansion.

DIVISION POINT - One of a number of sections of a large railroad, run as an indepentent entity to the extent of having its own fleet of locomotives, engines, and repair shops, officials, and clerical and operating personnal.

"DOG-LEG" - Railroad parlance for a sharp reverse curve in the track. The term's basis is the comparable crooked appearance of a dog's hind legs.

DOUBLE-ACTING ENGINE - An engine in which steam is directed alternately into the two ends of a closed cylinder, eliminating unpowered return strokes of the piston.

DOUBLE-ENDER - A locomotive able to run in either direction. Robert Fairlie of Ireland designed the most widely adopted double-ender in 1866, an 0-4-4-0 that had twin boilers with a central fire box and cab, and a trucklike cylinder and driving wheel assembly beneath each barrel for flexibility.

"DRAG" - A slow freight train.

DRIVING AXEL - An axel on which the driving wheels are mounted .

DRIVING BOX - A housing containing the bearing for a driving axel.

DRIVING UNIT - An assembly of cylinders, valve gear, rods, driving wheel and brakes mounted on or attached to an engine bed.

DRIVING WHEEL - One of the wheels of a locomotive that is connected to the main or side rods and transforms the engine's power into traction.

"DUMPING THE AIR" or "DYNAMITING HER" - Uncovering all the openings in the control valve of an airbrake system at once in an emergency, to apply its full force.

DUPLEX AIR COMPRESSOR - An air compressor developed about 1910, capable of compacting as much as 150 cubic feet of air a minute to the 140-pound pressure at which it was delivered to the main reservoirs. The duplex contained two steam cylinders and two compound air cylinders.
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E

ECCENTRIC - A circulat plate with a slightly off center hole, mounted on a driving axle. Eccentrics were used on most early locomotives to actuate the valve gear mechanism controlling forward and backward motion.

EJECTOR - A device for exhausting air in a vacuum brake, used in the latter 19th century.

ENGINE BED - The underframe assembly of a locomotive.

EQUALIZER - A beam that connects two axle springs to distribute the weight of the car or locomotive evenly.
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