Changes

[[Image:Reversible rail.jpg|thumb|right|250px|A reversible rail now used as a post.]]

[[Image:Reversible rail.jpg|thumb|right|250px|A reversible rail now used as a post.]]

Rails are usually made of steel, and in cross-section are usually shaped roughly like the capital letter "I", except that the top part (the "head") is much thicker than the bottom part.

Rails are usually made of steel, and in cross-section are usually shaped roughly like the capital letter "I", except that the top part (the "head") is much thicker than the bottom part.

These rails are known as ''flat-bottom'' rails.

These rails are known as ''flat-bottom'' rails. In the United States this type of rail is called "T" rail.

Another type of rail is symmetrical in cross-section, or nearly so, with two "heads".

Another type of rail is symmetrical in cross-section, or nearly so, with two "heads".

However, similar rails, known as ''bullhead'' rails, continued to be made and used, mainly in Britain, which used the same fittings as the reversible rails.

However, similar rails, known as ''bullhead'' rails, continued to be made and used, mainly in Britain, which used the same fittings as the reversible rails.

Yet another type of rail is [[tram|tramway]] rail, which is similar to flat-bottom rail but with a larger head containing a groove for the flange of the wheel.  These rails are designed to be laid flush with the surface of roads with the groove for the wheel flange contained in the head of the rail.

Yet another type of rail is [[tram|tramway]] rail, which is similar to flat-bottom rail but with a larger head containing a groove for the flange of the wheel.  These rails are designed to be laid flush with the surface of roads with the groove for the wheel flange contained in the head of the rail. This type of rail is called "girder" rail in the United States.

Rails are made in various sizes.

Rails are made in various sizes.

=== Baseplates ===

=== Baseplates ===

Baseplates (US: fishplates) are the metal plates placed between sleepers and rails.

Baseplates (US: tieplates) are the metal plates placed between sleepers and rails.

They serve to spread the weight of the rail out over a larger area of the sleeper, and to provide a small camber to the rail.

They serve to spread the weight of the rail out over a larger area of the sleeper, and to provide a small camber to the rail.

==== Spikes ====

==== Spikes ====

Large spikes (sometimes known as ''dogspikes'', probably from the shape of the head in some versions) are sometimes used to attach rails (or baseplates) to the sleepers.

Large spikes (sometimes known as ''dogspikes'', probably from the shape of the head in some versions) are sometimes used to attach rails (or baseplates) to the sleepers.  

The spikes have a head that protrudes from one side of the spike, and this head overlaps the base of the rail.

The spikes have a head that protrudes from one side of the spike, and this head overlaps the base of the rail.