What is a...?

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Railroads use many unique names and terms which are not common to daily life. Some of these terms are carried down over 180 years of railroad development. Here are a few:


Cattle Guard. A cattle guard was a wooden framed device which was constructed at a highway or farm crossing of a railroad. The slats on the guard prevented cattle or horses from entering the railroad track/property (but it allowed them to cross using the road).


Diamond. A diamond is a nickname for a short length of track where two railroad lines cross. The shape of the tracks are a diamond, particularly when they cross at an angle.

Dispatcher. Most railroads always had one or more dispatchers on duty, who controlled the movement of passenger and freight trains. Until the middle of the 20th century, the dispatcher used telegraph and telephone to accomplish this, with support of tower operators and station agents, using timetables and train orders. In Michigan, the Michigan Central has dispatchers in Detroit, Jackson, Bay City and Chicago. See also Yard Dispatcher.


Electrically Locked Switches. These are manually thrown main line switches where the switch must be unlocked before use. It is normally the dispatcher that unlockes the switch but in some cases, the unlock request set main line signals to stop and provided a run-off timer giving trains time to stop. After the timer finished, the switch could be opened.


Flag Stop. A flag stop was a location where passenger trains were given permission to stop to pick up or drop off passengers. These were usually small towns and many didn't have a depot or station agent.

Fusee. Also called a "flare", a fusee is a stick which looks similar to a stick of dynamite. Each stick has a removable cap which has a striking pad on the tip which ignites the fusee similar to a match. Fusees for railroad service came in 5 and 10 minute duration, and usually burned a bright red color. When lit, they were used to signal engineers and operators of other trains. Flagman at the rear of trains would leave a lit fusee on the ground when departing a stopped location. This would warn following trains that another train was a close as five minutes ahead. In double track territory, a fusee lit on a locomotive signaled an opposing train on the other track to stop. Fusee's required careful operation, because the ignited chemical dripped and could burn the user or enter a boot causing burns.


Gas Turbine Electric Locomotives. Gas turbine electric locomotives were tested and refined in the 1930's and 1940's as an alternative to steam locomotives. Many of these locomotive turbines burned fuel oil  which were coupled to D.C. generators which fed electric traction motors. Other examples burned coal. All were scrapped in the 1960's. General Electric was involved in these tests.

Golden Spike. A spike is a metal wedge device which holds the base of a rail to the tie below. It is pounded or mechanically pushed into the tie, usually with a tie plate. A "golden" spike was a ceremonial spike, which was used to signify the completion of a railroad line. Sometimes an electric connection was made when the spike was pounded in place and sent down the media's telegraph line to far off places. The most celebrated golden spike was used when the transcontinental railroad was completed at Promontory, Utah. But there were other examples on other lines.


Half-Interlocker. A half interlocker was used to control the crossing of two railroad tracks (see Interlocker below), however a half-interlocker had a signal system on the busier railroad, and derails on the other railroad. These were less expensive to use than full interlockers, and were often used when electric interurban or trolleys crossed main line steam railroads. Typically, the motorman on the electric line requested passage by unlocking the derail. This set the signals on the main roadroad to stop and there was often a time limit before the motorman could remove his derails. This was known as a "time lock".

Head-In Signal. A head-in signal was a second target signal on a block signal mast. When blinking white, it was a message for the approaching engineer to stop and call for instructions. The instructions were almost always to enter the passing track at the next siding to clear for another train. The head-in signal was turned on and off by the dispatcher using the same encoder which called towers along the line.

HotboxA hot box is an overheated wheel journal.  The journal is located in a box which protrudes slightly from the wheel assembly.  The box, which normally has a cover over it, is filled with "waste", which is oil-soaked to keep the journal cool.  An overheated journal is a serious situation, because a hot axle can fail, and break.  Hotboxes often caught fire, and smoked or sparked.


Interlocker. An interlocker is a mechanical or electronic system which prevents collisions and derailments at crossings, junctions, and crossovers along railroad lines. Most early interlockers were mechanical and used a "locking bed" of bars inside line manned towers at these locations. Others were ground lever locking systems and later electronic microprosssors operated from long distances away. Interlockers were also used to control trains at drawbridges. Main railroads had partial interlockings, which controlled routing but did not always prevent collisions, such as allowing entry to blocks which were not signaled. Interlockers were not fool proof and stilled caused many fatal collisions and derailments.

Iron Man. An Iron Man is a device, about 15 feet tall and mounted into a concrete base at the side of the track near a signal station.  The device has at least two arms which swing up to a horizontal position.  These arms hold folded train orders in a string.  When the train passes by, the engineer and conductor grab the train orders by putting their arms through the strings.  This way, they can get their train orders without stopping.


Passing Sidings. Also called passing tracks, these extra tracks were designated in timetables and were normally kept clear of cars for the purpose of passing another train. On double track, these sidings were often used to pull off so that a train of a higher class could pass. Almost every town in Michigan had a passing siding and occasionally more than one. The length of passing sidings depended on the length of freight trains during period the siding was built.  As an example, a passing siding on the Michigan Central main was was perhaps 130 car lengths (44' cars at the time), or about a mile long. But on the Ypsilanti Branch the longest passing siding was 23 car lengths, or 1,012 feet long.


Rip Track. A rip track was a short yard track used for placement of freight cars which needed repair.

Roadmaster. A roadmaster on a railroad supervised the operations of locomotives, which included troubleshooting and scheduling of motove power. This position was also known as the Road Foreman of Engines.

Running Wild. Running "Wild" was a situation when a train was given permission to operate between the schedules of regular trains on a route listed in the timetable. Around 1895, this term was replaced with running "extra" or running "irregular" for freight trains and running "special" for extra passenger trains. [PHTH/4-11-1895]


Smash Board. A smash board was a signaling device located at either end of some river drawbridges. Most drawbridges had semaphone or target signals which governed train passage of the bridge. But the smash board was a larger semaphone like device which dropped down in the right-of-way. Though it would not stop a train from entering an open bridge, it was visable from a longer distance away.  An engineer who hit a smash board was like destined to be at the bottom of the river bed within seconds and it was probably a good time to jump to safety. The MCRR had smash boards at Bay City, over the Saginaw River.

Spring Switch. Most switches are lined and locked into position by the dispatcher or a train crew member. Spring switches were normally used at the begining and/or end of a passing siding.  Even though the switch may have been lined for the non-diverging route, a train in the other direction could, with permission, "run through" the switch and proceed out of the siding. The rails in the switch would return back to the normal route after the wheels of the car passed. It was important not to stop on a spring switch and then back up, as the train would likely derail. Spring switches were usually identified in the employee timetable. Though they are must less common (because of CTC), some railroads in Michigan continue to use them.

Station Semaphore. Most stations had semaphores which were used as block signals and train order signals. But some stations had advanced station semiphores which were placerd approximately 1,000' on either side of the station. These signals, operated remotely by the station agent, protected trains or switch moves which were occupying the main track at the station. Mackinaw City, at the north end of the MC/NYC Mackinaw Branch, had an automatic station semaphore for northbound trains entering the town warning them if there was a train ahead (at the station) on the main track.

Switch Stand Targets. Almost all switches had a switch stand, which contained the lever for changing the route of the track. Some of these were short and used in low speed yard tracks. Others, on the main line, were 8'-10' tall and had painted directional signs or lighted indicators indicating which direction the switch was set. In the early 20th century, almost all main line switch stands were lighted using kerosene oil lamps. Later, some of these were lighted with low voltage bulbs. As time passed, low volume branch line switch stands were allowed to be unlit, and identified as such in the employee timetable. Today, the targets have reflective paint.


Torpedo. A torpedo is a device which is strapped to the top of a rail.  When a train drives over the torpedo, it emits a very loud "bang" which can be heard over the noise of the engine, and signals the engineer to stop immediately.  Torpedo's are generally placed by the flagman when protecting a train ahead.  Torpedo's are about 2" x 2", red, about 3/4" high, and have two lead straps attached which hold it to a rail.  The torpedo has discs inside and are filled with detonating powder.  The Torpedo was invented about 1874. Note: Torpedos may contain nitroglycerine and can become unstable, particularly if they have moisture on them. If you find a torpedo, contact your local police or fire department.

Track Pan. A track pan was a long, box like trough built between the rails with an open top. The box, or "pan" was filled with water. When a moving steam locomotive came over the pan, it lowed a scoop and water rushed from the pan up into the tender of the locomotive. This enabled-scooop equipped steam locomotives to take on water without stopping. For more information about track pans, click on this link.

Trainmaster. A trainmaster was railroad division field supervisor, who normally reported to the division superintendent and facilitated train operations.

Train Order. Train orders were written instructions given by the dispatcher to block operators, conductors and engineers for the purpose of controlling trains. They were nicknamed "flimsies" because of the lightweight tissue paper they were written on. Train orders were used for granting permission to use a particular track, to change a train's timetable schedule, to reduce speed, to hold a train at a location, to set up a passing of trains, to open or close a particular station, and so on. They were usually given by the tower operator to both the head end (enginerer) and rear end (conductor) of a train through a string-hoop system. Passenger trains often had a third copy delivered to the flagman. Form 19 train orders were the most commonly used, but a Form 31 order required hand delivery to a stopped train - usually when it was necessary to take away the timetable rights of a train. The format of train orders was established in rule books or timetables. Today, train orders no longer exist and have been replaced by mandatory directives or NORAC Form D's given by radio.

Train Order Signals. Train order signals were used at stations, crossings and towers and designated in the employee timetable. When the signal was lit, the engineer and conductor new to pick up a train order and other forms. These signals were attached to the normal signal mast (usually top right), on their own mast, or attached to the station roof or tower. They were operated by the station agent or tower operator on the direction of the dispatcher. If a station was closed for the night, the train order "board" was normally set for proceed, or "no orders".


Wye. A wye is a three legged track which is used for turning engines and other cars. These were particularly important in the days of steam engines which were able to operate at high speeds only in forward movements. Even small towns, such as New Hudson on the GTW's Jackson branchline, had a small wye for turning locomotives.

Dispatcher. The Yard Dispatcher controlled the movement of trains in large terminals. In Michigan, the only railroad to have a Yard Dispatcher was Detroit, covering operations from Windsor to Town Line, and from River Rouge yard north to North Yard. In early years, the Yard Dispatchers issued train orders but in later years instructions were verbally given and main tracks were governed by signals.

Yard Limit. The Yard Limit defines the extent of the yard or terminal. They were normally posted by a yard limit sign. Trains in yard limits were required to clear for scheduled trains (listed in the timetable). But extra freight trains, pullers and yard engines were given more latitude on main line and yard tracks. All trains, except for scheduled trains, were required to proceed with the ability to stop in a clear distance ahead, prepared to find another train on the track or switches left open. The biggest yard limit in Michigan was the MC's Detroit terminal. But there were hundreds of other smaller yard limits on the MC and other roads.