Now the naval machine is composed of many machines, but the machines that have to be "operated" in war, using the word "operated" in the usual military sense, are only the active fleet, the bureaus and offices and the bases; including in the bases any navy-yards within them. Using the word "operated" still more technically, the only thing to be operated in war is the fleet: but the head of the Navy Department must also so direct the logistical efforts of the bureaus and offices and bases, that the fleet shall be given the material in fuel, supplies, and ammunition with which to conduct those operations. Like the chief engineer of a ship, he must both operate and maintain the machine. The fleet itself is a complex machine, even in time of peace. In war time it is more so, for the reason that many additions are made to the fleet when war breaks out; and these additions, being largely of craft and men held in reserve, or brought in hurriedly from civil life, cannot be so efficient or so reliable as are the parts of the fleet that existed in time of peace. The active fleet consists of battleships, battle cruisers, cruisers of various speeds and sizes, destroyers, submarines, and aircraft. The fleet is under the immediate command of its commander-in-chief, just as the New York naval station is under the command of its commandant; but the commander-in-chief of the fleet is just as strictly under the command of the head of the admiralty or Navy Department as is the commandant. The commander-in-chief is the principal part of the naval machine that is operated in war; and the ultimate success of the naval machine in war depends largely on the amount and degree of understanding that exists between the commander-in-chief and the head of the Navy Department. That goodwill and kindly feeling should exist between them may be assumed, since both have the same object in view; but that real understanding should exist between them is more difficult to assume, especially if they have been trained in different schools and have not known each other until late in life. In the latter case, misunderstandings are apt to arise, as time goes on; and if they do, the most cordial good feeling may change into mutual distrust and suspicion, and even hatred. To see that such things have happened in the past, we do not have to look further back in history than the records of our own Civil War, especially the records of the mutual relations of the head of the War Department and some generals. That a situation equally grave did not exist between the head of the Navy Department and any of the admirals may be attributed to the fact that the number of naval defeats was less than the number of defeats on land, to the lesser number of persons in the navy, and to the smaller number of operations. Perhaps a still greater reason was the greater confidence shown by civilians in their ability to handle troops, compared with their confidence in their ability to handle fleets.