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Porcelain Third Rail Insulators

Third rail insulators were used to insulate electric railways that use an additional track to provide the power to trains.  These installations tended to be cleaner looking than the catenary required for overhead power distribution but have the disadvantage of having the powered track accessible where people can be injured.  The Ohio Brass company made a number of third rail styles.

This illustration shows some applications for third rail insulators. 

A relatively modern third rail insulator in use.

Here are two views of an early porcelain third rail insulator.  To the right is an illustration of how these were used.


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