When the allied fleets had started their bombardment of the Turkish forts at the Dardanelles they were breaking certain well-defined rules which had been axiomatic with naval authorities. The greatest of modern battleships were designed to fight with craft of their like, but not to take issue with land fortifications. For weeks, while the fleets succeeded in silencing for a time some of the Turkish forts, it was thought that this rule no longer held good. But when, after March 19, 1915, the fleets ceased attempting to take the passage without military cooperation, the worth of the rule was reestablished. The ease with which the bombarding ships were made victims of hostile submarines was greatly instrumental in making the rule again an axiom. The naval supremacy of the allied powers brought them certain advantages--advantages which they had without winning a decisive victory. Germany and Austria were cut off from the Western Hemisphere, and were troubled, in consequence, by shortage in food for their civilian populations to a greater or lesser degree. This was perhaps a negative benefit derived by the Allies from their naval supremacy; the affirmative benefit was that their own communications with the Western Hemisphere were maintained, enabling them not only to get food for their civilian populations, but arms and munitions for their armies; and even financial arrangements, which, if their emissaries could not pass back and forth freely could not have been made, depended on their control of the high seas. They were able to keep the Channel clear of submarines long enough to permit the passage of the troops, which England from time to time during the first year of the war sent to the Continent, and permitted the participation of the troops of the British overseas dominions, the troops from Canada joining those in France, and the troops from New Zealand and Australia taking their places in the trenches along the Suez Canal and on the Gallipoli Peninsula. Thus, to a certain extent, the advantage of continuous railroad communication which was enjoyed by the Teutonic allies "inside" the arena of military operations was offset by the naval communication maintained by the Entente Powers "outside" the arena of military operations. * * * * * CHAPTER XXI FIGHTS OF THE SUBMARINES