Because the cottage is at the lock where the canal commonly called the Huddersfield Broad Canal joins the C&H. The name of the canal when it was built was Sir John Ramsden’s Canal. In the same way that the canal commonly called the Huddersfield Narrow Canal was the Huddersfield Canal when it was built, later the Huddersfield & Manchester Railway and Canal Company.
Sir John Ramsden was a major player in 18th century Huddersfield, commemorated in Ramsden Street among other places. I learned to swim at Ramsden Street baths.