north of Ireland through the North Channel and down the
Irish Sea to Liverpool. Under certain conditions these
convoys passed south of Ireland and thence up the Irish
Sea. The convoys to the east coast took a trunk line that
passed up the English Channel. Practically all shipping
from the United States to Great Britain and France took
one of these trunk lines. But, like our railroad systems,
each of these main routes had branch lines. Thus shipping
destined for French ports took the southern route until off
the entrance to the English Channel; here it abandoned
the main line and took a branch route to Brest, Bordeaux,
Nantes, and other French ports. In the Channel likewise
several "single-track" branches went to various English
ports, such as Plymouth, Portsmouth, Southampton, and
the like. The whole gigantic enterprise flowed with a
precision and a regularity which I think it is hardly likely
that any other transportation system has ever achieved.
IV
A description of a few actual convoys, and the experiences of our destroyers with them, will perhaps best make clear the nature of the mechanism which protected the world's shipping. For this purpose I have selected typical instances which illustrate the every-day routine experiences of escorting destroyers, and other experiences in which their work was more spectacular.
One day in late October, 1917, a division of American destroyers at Queenstown received detailed instructions from Admiral Bayly to leave at a certain hour and escort the outward convoy "O Q 17" and bring into port the inbound convoy "H S 14." These detailed instructions were based upon general instructions issued from the Admiralty, where my staff was in constant attendance and co-operation. The symbols by which these two groups of ships were designated can be easily interpreted. The O Q simply meant that convoy "No. 17"—the seventeenth which had left that port was Outward bound from Queenstown, and the H S signified that convoy "No. 14 " was Homeward bound from Sydney, Cape Breton. Queenstown during the first few months was one of those places at which ships, having discharged their cargoes, assembled in groups for despatching back to the United States. Later
