Sough
Black's Law Dictionary · Henry Campbell Black, M.A. · 1910
Black's Law Dictionary
In English law
A drain or water-course. The channels or water-courses used for draining mines are so termed; and those mines which are near to any given sough, and lie within the same level, and are benefited by it, are technically said to lie within the title of that sough.
5 Mees. & W. 228; Brown.