The work of preparing all that part of the naval machine which in time of peace is separate from the active fleet is purely one of logistics; it is that part of the preparation which calculates what ways and means are needed, and then supplies those ways and means. Logistics, having been told by strategy what strategy plans to do, calculates how many and what kinds of vessels, men, guns, torpedoes, fuel, food, hospital service, ammunition, etc., are needed to make possible the fulfilling of those plans; and then proceeds to provide what it has calculated must be provided. This does not mean that strategy should hold itself aloof from logistics and make arbitrary demands upon it; for such a procedure would result in making demands that logistics could not supply; or, through an underestimate of what logistics can supply, in refraining from demanding as much as could be supplied. Logistics, of course, does provide what strategy wants, in so far as it can; but in order that satisfactory results may be obtained, the fullest co-operation between strategy and logistics is essential; and to this end frequent conferences are required between the officers representing both. The logistic work of expanding the naval forces to a war basis may evidently be divided into two parts: the adding of vessels and other craft appropriately equipped and manned to the active fleet, and the establishment of a coast-defense force, which will be distributed along the coast and divided among the most important commercial and strategic centres.