On the assumption that a close blockade, either of the Heligoland Bight or of the exits from the Baltic, is not possible, the Admiralty cannot guarantee that individual vessels will not frequently slip through the cruiser squadrons patrolling the wide area of the North Sea. The North Sea comprises an area of more than 125,000 square miles. The number of cruisers available is less than 30, of which a large proportion will always be recoaling. The aid that can be given at a distance from the British shore by torpedo craft would be partial and fleeting. The weather is frequently thick; on a third of the days in the year the visibility is not more than 4 miles; on a quarter of the days in the year it is not more than 2 miles. There are about five days fog per month during the year. April averages ten days fog. At night it is frequently impossible to see a ship without lights at more than a few hundred yards distance, and often not at that. It is no exaggeration to say that the main risk which a single fast ship would run, steaming at night without lights, would be that of collision, which chance may be very well accepted. It will be easy to demonstrate this by experiments at the forthcoming manœuvres. If, therefore, close and certain observation becomes impossible, there is a very good chance of an indefinite succession of individual transports reaching the British coasts without being intercepted by the controlling cruiser squadrons. Let us now consider what arrangements exist or are possible along the line of the British coasts to detect and attack such vessels. Four flotilla cruisers, seventy-four destroyers and torpedo-boats, and eighteen submarines are placed under the command of the Admiral of Patrols for the defence of the East Coast from the Shetlands to Dover; less than 100 vessels and more than 600 miles of sea front. It is quite impossible with such a small force to maintain a regular patrol, or still less a line of observation. These flotillas are not intended for observation, but to attack. To employ them on the former service, for which their numbers are wholly insufficient, would speedily exhaust them: at least half would have to be resting and refuelling. It is not possible with the forces available for the patrol flotillas to prevent enemy vessels from reaching the British coast. Our dispositions are intended to make it certain that they will be attacked in force with the least possible delay.