The problem of getting into service the ships that are to be gotten from the merchant service is more difficult, and is perhaps of more importance; that is, it is more important to get into the service some vessels from the merchant service than some reserve ships; more important, for instance, to get colliers to serve the fleet with coal than to commission some antiquated cruisers.  Naturally, the number and kinds of ships that need to be provided will depend on the nature of the war—­whether, for instance, a very large force is to be sent to the other side of the world, to meet a powerful fleet there, or whether a sudden attack on our Atlantic coast is to be repelled.  The difference, however, is largely numerical; so that if the plans provide for a sufficient number to take part in the distant expedition, it will be easy to get the appropriate number to meet a coast attack.

To receive an attack upon the coast, however, provision must be made for vessels and men not needed on an expedition across the seas—­that is, for vessels and men that will defend the coast itself from raids and similar expeditions.

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.