So many vessels were sunk that our reserve of oil fuel became perilously low.

Instead of a reserve of some five or six months we were gradually reduced to one of about eight weeks, and in order to economize expenditure of fuel it actually became necessary at one time to issue directions that the speed of oil-burning warships was to be limited except in cases of the greatest urgency.

Such an order in war was a matter of much gravity; the great majority of our light cruisers and destroyers were fitted to burn oil fuel only, as well as our latest and most powerful battleships.

The crisis was eventually overcome by drawing upon every source (including the Grand Fleet) for destroyers to escort the tankers through the submarine danger areas, and by the assistance given us by the Ministry of Shipping in bringing supplies of oil fuel to this country in the double bottoms of merchant ships.

By the end of 1917 the situation had greatly improved.
The losses of shipping during 1917 were particularly heavy in the Mediterranean.