The Cooktown had just discharged her second pattern.  They had to hit the Jap hard and fast, with pattern after pattern, each set to a different depth to ensure they caught the target. But only one thrower fired from the side nearest the Jackal. But nothing at all was flung from the other side.  They had to get this Jap. If they failed there was only a useless corvette between the submarine and six fat-bellied merchantmen…