In the adoption of the convoy system the Royal Navy was embarking on no new venture. Modern ships and weapons may have brought a novel complication to this old form of sea-guardianship, but there is little in seafaring for which the traditions of the Naval Service cannot offer text and precedent. The constant of protection by convoy has remained unaltered by the advance of armament and the evolution of strange war craft: the high spirit of self-sacrifice is unchanged. When, in October 1917, the destroyers _Strongbow_ and _Mary Rose_ accepted action and faced three German cruisers, their commanders--undismayed by the tremendous odds--reacted the parts of the common sea-dramas of the Napoleonic wars. The same obstinate courage and unconquerable sea-pride forbade them to desert their convoy of merchantmen and seek the safety that their speed could offer. H.M.S. _Calgarian_, torpedoed and sinking, had yet thought for the convoy she escorted. Her last official signal directed the ships to turn away from the danger. [Illustration: BUILDING A STANDARD SHIP] The convoy system did not spring fully served and equipped from the earlier and less exacting control. Tentative measures had to be devised and approved, a large staff to be recruited and trained. The clerical work of administration was not confined to the home ports; similar adjustment and preparation had to be conducted in friendly ports abroad. As naval services were adapted to the new control, the system was extended. The comparatively simple procedure of sending destroyer escorts to meet homeward-bound convoys became involved with the timing and dispatch of a mercantile fleet sailing from a home port. The escorts were ordered out on a time-table that admitted of little derangement. Sailing from a British port with a convoy of outward-bound vessels, the destroyers accompanied that fleet to a point in the Atlantic. There the convoy was dispersed, and the destroyers swung off to rendezvous with a similar convoy of inward-bound vessels. While the outgoing merchantmen were allowed to proceed independently after passing through the most dangerous area, the homeward-bound vessels were grouped to sail in company from their port abroad. An ocean escort was provided--usually a cruiser of the older class--and there was opportunity in the longer voyage for the senior officer to drill the convoy to some unity and precision in manoeuvre.