Chock Block
A cheap and simple alternative to catch points or a derail is a chock block, which is a piece of timber that can be positioned and locked over one of the rails at the end of a siding to protect the main line from runaways. In order for the siding to be used the chock block must be removed.
Read more about this topic: Catch Points
Famous quotes containing the word block:
“No contact with savage Indian tribes has ever daunted me more than the morning I spent with an old lady swathed in woolies who compared herself to a rotten herring encased in a block of ice.”
—Claude Lévi-Strauss (b. 1908)