The head of the organization was, of course, Rear-Admiral A.L.  Duff, the member of the Board and Staff immediately responsible also for the whole anti-submarine organization.  Only those who witnessed Admiral Duff’s work at the Admiralty during 1917 can realize the immense debt that the country owes to his untiring ability, patience, energy and resource.  Capt.  H.G.  Henderson, who had been associated with the convoy system from its start, was an invaluable assistant, as also was Commander I.W.  Carrington.  Capt.  Richard Webb, the Director of the Trade Division, and Capt.  Frederic A. Whitehead, the Director of the Mercantile Movements Division, took an important share in the work of organization, whilst the work of Convoy Manager was carried through with quite exceptional skill by Paymaster-Commander H.W.E.  Manisty.  These officers were assisted by most capable staffs, and the Ministry of Shipping, without whose assistance the work could not possibly have been successfully carried out, co-operated most cordially.

CHAPTER VI

THE ENTRY OF THE UNITED STATES; OUR NAVAL POLICY EXPLAINED

The entry of the United States of America into the war in April, 1917, had an important although not an immediate effect upon our Naval policy.  That the effect was not immediate was due to the fact that the United States Navy was at the time indifferently provided with the particular classes of vessels which were so greatly needed for submarine warfare, viz. destroyers and other small surface craft, submarines and light cruisers; further, the United States mercantile fleet did not include any considerable number of small craft which could be usefully employed for patrol and escort duty.  The armed forces of the United States of America were also poorly equipped with aircraft, and had none available for Naval work.  According to our knowledge at the time the United States Navy, in April, 1917, possessed twenty-three large and about twenty-four small destroyers, some of which were unfit to cross the Atlantic; there were about twelve submarines capable of working overseas, but not well suited for anti-submarine work, and only three light cruisers of the “Chester” class.  On the other hand about seven armoured cruisers were available in Atlantic waters for convoy duties, and the Navy included a fine force of battleships, of which fourteen were in full commission in April.

At first, therefore, it was clear that the assistance which could be given to the Allied Navies would be but slight even if all available destroyers were sent to European waters.  This was, presumably, well known to the members of the German Naval Staff, and possibly explains their view that the entry of the United States of America would be of little help to the Allied cause.  The Germans did not, however, make sufficient allowance for the productive power of the United States, and perhaps also it was thought