The Navy continued its co-operation with the Army in the _Salonika theatre of war_, assisted by the Royal Naval Air Service, and bombardments were continually carried out on military objectives. Similarly _in the Adriatic_ our monitors and machines of the R.N.A.S. assisted the military forces of the Allies; particularly was this the case at the time of the Austrian advance to the Piave, where our monitors did much useful work in checking enemy attempts to cross that river. _Off the Gallipoli Peninsula_ the Naval watch on the mouth of the Dardanelles was continued; extensive new minefields were laid during the year, and were effective in sinking the _Breslau_ and severely damaging the _Goeben_ when those vessels attempted a sortie on January 20, 1918. The R.N.A.S. during the year carried out many long distance reconnaissance and bombing operations over Constantinople and the vicinity. _In the Red Sea_ Naval operations were carried out in conjunction with friendly Arabs, and the Arabian coast cleared of Turkish forces. _In the White Sea_ during the latter part of 1917 the whole of the Naval work fell upon British Naval forces when the Russian ships, which had co-operated hitherto, had come under the influence of the political situation. Our force in these waters consisted largely of trawlers engaged in minesweeping and escort work. The latter duty imposed a very heavy strain on officers and men, involving as it did the safe conduct during the year of no fewer than one thousand ships carrying stores and munitions for the Russian military forces. _In the Baltic_ the situation became very difficult owing first to the Russian revolution and, finally, to the Russian debacle. Our force in these waters consisted of seven submarines. It became evident at the beginning of October, 1917, that the Germans were intending to carry out some operations in the Baltic against Russia, and the question of affording assistance was at once considered by the Naval Staff. It was surmised that but little dependence could be placed on the Russian Baltic Fleet (events showed this surmise to be accurate), and in order to keep our control over the North Sea and ensure the safety of our communications with France it was obvious that for any action we might decide to take we should be obliged to divide the Grand Fleet, sending such portion of that Command into the Baltic as could successfully engage the High Sea Fleet if encountered, as well as to secure the return passage via the Great Belt, and retaining a sufficient force to deal with such German vessels as might attempt operations in the North Sea or Channel during our raid into the Baltic.