On the 28th the 2nd Battle Cruiser Squadron, with two ships of the 1st Light Cruiser Squadron, the 2nd Light Cruiser Squadron, the 4th Light Cruiser Squadron, and 14 destroyers of the 1st and 4th Flotillas from Rosyth and Scapa, together with Commodore Tyrwhitt and four light cruisers and 12 destroyers from Harwich, left their bases to carry out an operation in the Skagerrak, with the object of intercepting trade and searching for any enemy vessels. Only one German vessel (a trawler) was encountered, and she was sunk after removal of the crew. A Danish steamer was sent in to a British port with a guard on board and the force returned to their various bases on the 31st. As the threatened coal strike limited the movements of the coal-burning heavy ships, the oil-burning destroyers were used for anti-submarine work to a greater extent than would have been desirable if greater activity of the Fleet had been anticipated. Operations against enemy submarines included: On July 1st the _Hampshire_ reported that a torpedo had been fired at her in the Moray Firth. Twelve destroyers and all available local patrol vessels were sent to endeavour to locate and sink the submarine. The steamboats from the ships at Cromarty were also despatched to operate in the various bays in the Moray Firth, where a submarine might elect to lie on the bottom. The boats exploded a large number of charges on the bottom in the hope of forcing any submarine to the surface. The operations were abandoned on the evening of the 2nd, the submarine not having been located. On the 4th a division of the 2nd Flotilla hunted for another submarine reported in the Moray Firth. From the 5th to the 10th the sea-plane carrier _Campania_, with a flotilla leader, eight destroyers, four sloops and a large number of trawlers and net-drifters, operated against submarines that were reported to be passing through the Fair Island Channel, being based on Pierowall Harbour, in the north of the Orkneys. The destroyers, sloops and patrol vessels operated in conjunction with the sea-planes. No success was achieved, however, although these extensive operations covered a large area. On the night of the 16th a division of destroyers operated against a submarine reported to the southward of the Pentland Firth, off Duncansby Head, but again without result.