The next case is also typical, being a patrol action; but it differs from the last in that the success was due to combined work by three destroyers, and not only by a single crew. There are also one or two exceptional circumstances which distinguish it from other actions of a similar kind--the presence of the Rear-Admiral commanding the local force, and the additional evidence which eventually settled the classification of the result. It was on the morning of a day in March 1918 that a light-cruiser squadron was cruising in the North Sea; and at 9.25 A.M. three destroyers--_Thruster_, Commander A. D. Gibbs; _Retriever_, Commander E. W. Taylor; and _Sturgeon_, Lieutenant-Commander Henry Coombs--were ordered to take up a screening position ahead of the force. As they were in the act of moving to their stations an object was sighted, two points on _Sturgeon’s_ port bow, and about one mile distant. A moment afterwards it was recognised as the conning-tower of a submarine. In order to understand what followed, it is necessary to have the positions clearly before the mind’s eye. _Thruster_ and _Retriever_ were immediately ahead of the squadron, to starboard and port respectively, and _Sturgeon_ was ahead of the flotilla, in the act of crossing from starboard to port. She had just passed _Thruster_ and was on her port bow, going towards a point ahead of _Retriever_, when she sighted the submarine on her own port bow and therefore almost enclosed in the triangle formed by the three destroyers. The U-boat dived immediately, and _Sturgeon_ fired as she did so, but without effect--a late shot at a disappearing target. Lieutenant-Commander Coombs at once increased to full speed, and altered course to pass over the position. He arrived accurately, and in time to sight the track of the submarine as she tried to bolt through the only opening left to her, between her pursuer and the advancing _Retriever_. Her under-water speed was quite unequal to this effort, and in a moment _Sturgeon_ was passing along her track and overhauling her. Another moment and the destroyer’s depth-charges, set to forty feet only, were dropped--one on either side of the track and a little ahead of it.