Thank you for the suggestions. Unfortunately I have looked at the fine When Liverpool was Dixie site, and Terry Foenander's extensive site, (both of these sent me off on new tangents of research) and others, plus lots of books and manuscripts. I wrote my masters thesis on blockade runner design, and have been pursuing various related lines of research in the US, Great Britain, Canada, Australia, France and other places for more than 20 years. There are no mentions of coal torpedoes in the standard first person accounts related to runners: Bullock; Tom Taylor; Watson; Wilkinson; Life of Captain Fry; any of the 3 versions of Hobart Pasha's autobiography; or in more modern general works: Wise; Bradlee; Horner; Nepveaux; Litz; Cochran; W.T. Block; Daddysman; Browning; Taylor; Buker, etc. And despite carefully examining the consular dispatches of perhaps 40 United States consular posts so far, none of them mentions coal torpedoes being used against blockade runners. Only one of Sprunt's books mentions the coal torpedoes being used against runners, Chronicles of the Cape Fear. He makes them sound like a fairly common problem for runner engineers, hence my question - I have no idea where to look next. I am hoping some reader of this might know of records in some local historical society or university well enough to recall mention of Yankee use of coal torpedoes. I would appreciate more suggestions.