It is, therefore, important to the comprehension of the changes effected in that period of transition, for which Hawke and Rodney stand, to recognize the distinctive lesson of each of these two abortive actions, which together may be said to fix the zero of the scale by which the progress of the eighteenth century is denoted.  They have a relation to the past as well as to the future, standing far below the level of the one and of the other, through causes that can be assigned.  Naval warfare in the past, in its origin and through long ages, had been waged with vessels moved by oars, which consequently, when conditions permitted engaging at all, could be handled with a scope and freedom not securable with the uncertain factor of the wind.  The motive power of the sea, therefore, then resembled essentially that of the land,—­being human muscle and staying power, in the legs on shore and in the arms at sea.  Hence, movements by masses, by squadrons, and in any desired direction corresponding to a fixed plan, in order to concentrate, or to outflank,—­all these could be attempted with a probability of success not predicable of the sailing ship.  Nelson’s remarkable order at Trafalgar, which may almost be said to have closed and sealed the record of the sail era, began by assuming the extreme improbability of being able at any given moment to move forty ships of his day in a fixed order upon an assigned plan.  The galley admiral therefore wielded a weapon far more flexible and reliable, within the much narrower range of its activities, than his successor in the days of sail; and engagements between fleets of galleys accordingly reflected this condition, being marked not only by greater carnage, but by tactical combinations and audacity of execution, to which the sailing ship did not so readily lend itself.

When the field of naval warfare became extended beyond the Mediterranean,—­for long centuries its principal scene,—­the galley no longer met the more exacting nautical conditions; and the introduction of cannon, involving new problems of tactics and ship-building, accelerated its disappearance.  The traditions of galley-fighting, however, remained, and were reinforced by the habits of land fighting,—­the same men in fact commanding armies on shore and fleets at sea.  In short, a period of transition ensued, marked, as such in their beginnings are apt to be, by an evident lack of clearness in men’s appreciation of conditions, and of the path of development, with a consequent confusion of outline in their practice.  It is not always easy to understand either what was done, or what was meant to be done, during that early sail era; but two things appear quite certainly.  There is still shown the vehemence and determination of action which characterized galley fighting, visible constantly in the fierce effort to grapple the enemy, to break his ranks, to confuse and crush him; and further there is clear indication of tactical plan on the grand scale, broad in outline and combination, involving different—­but not independent—­action by the various great divisions of the fleet, each of which, in plan at least, has its own part, subordinate but contributory to the general whole.