I — M

King-bolt/King-pin.  (See Center-pin.)

Letter-board.  Horizontal board or fascia extending the length of the car just below the eave line (and generally above the windows) on which the name or initials of the company owning the car are displayed.

Lookout.  A small cupola or upper deck in the roof of a caboose to enable trainmen to keep a lookout over the train. In the 19th century and early 20th, also used to display signals to the locomotive or to following trains.

Mail Catcher.  A “V”-shaped device mounted across the doorway of a railway mail car to take up or “catch” a mail bag while the car is in motion. (Illustration to right assumes train is moving to the left.) The mail catcher is pivoted horizontally on either side of the door so that when the mail clerk pulls the handle inward and down to a position parallel to the floor of the car, the arm (down in this illustration) is raised and protrudes from the side of the car. The mail bag is shaped like an hour-glass, and suspended in a vertical position between two arms that extend toward the track. The open end of the mail catcher hooks the middle of the bag and funnels the bag inward toward the car, where it catches in the crook at the bottom of the “V” (to the right in illustration) and is retrieved by the mail clerk. [We are looking for images showing a mail bag and demonstrating how the catcher works. If you know of any, please contact us.]

Main Carline.  (See Carline.)

Miller car coupler.  (also Miller Hook, Miller platform) An arrangement for coupling cars automatically, consisting of two heavy iron hooks that act as draw-bars and which are made to engage with each other by two springs when the cars come together.

Miller platform.  An end platform designed by Ezra Miller and arranged so that the pulling and pushing strains on the car are in direct line with the sills of the car. This is generally facilitated by placing the end platform on an extension of the car frame rather than on projecting timbers fastened below the car body. (See also the Miller Hook page.)
 

Monitor roof.  (below) The earliest type of passenger car or streetcar roof with a raised clerestory or center section to let in light and/or ventilation, as opposed to a flat or arched roof.  Strictly speaking, a true monitor roof is one with vertical ends as distinct from a bullnose roof or duckbill roof roof where the clerestory tapers into the platform roof.