I have started work on a study of the Cavan and Leitrim Railway and hopefully the first post on the two main lines will be ready soon. While I was reading various sources on-line and Patrick Flanagan's book about the line, I became aware of a series of attempts to extend the tramway which ran from Ballinamore to Arigna through to Sligo. None of these attempts was successful.
In the end an extension line was built to aid transport of coal from the Arigna mines down to the tramway station. This extension was under 5 miles in length and was soon truncated to a much shorter version. It was known as the Arigna Valley Railway.
The story is worth reading. For much of it I am indebted to Patrick Flanagan and his contributions are referenced throughout.