P

Passing Track
A track which is auxiliary to the main track for meeting or passing trains. Also referred to as a siding.

Penetration
The depth to which preservatives enter wood.

Piped Rail
One with a vertical split usually in the web.

Plug, Tie
Rectangular sections of wood for filling unused spike holes in wood ties.

Point Rail
Switch rail or switch point - the tapered rail of a switch used to divert traffic along either route of a turnout.

Point of Switch (Actual)
The end of the switch point that is furthest from the frog. The narrow part of the switch point.