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Incising
Puncturing the longitudinal surface of poles, ties, and timbers to assure penetration by a preservative and to relieve surface tension as an aid in the control of checking.
Insulated Switch
A switch in which the fixtures, principally the gage plates and the switch rods connecting or reaching from one rail to the opposite rail, are provided with insulation so that the electric track circuit will not be shunted.
Insulation
A device or material that prevents the flow of electric current in a track circuit from passing from one rail to the other or through switches and other track structures.
Puncturing the longitudinal surface of poles, ties, and timbers to assure penetration by a preservative and to relieve surface tension as an aid in the control of checking.
Insulated Switch
A switch in which the fixtures, principally the gage plates and the switch rods connecting or reaching from one rail to the opposite rail, are provided with insulation so that the electric track circuit will not be shunted.
Insulation
A device or material that prevents the flow of electric current in a track circuit from passing from one rail to the other or through switches and other track structures.
