CHAPTER V.
THE CONVOY SYSTEM AT WORK As has been mentioned in Chapter II., the first ships to be brought under a system of convoy were those engaged in the French coal trade and in the trade between Scandinavia and the United Kingdom.
In the case of the _French coal trade_, commencing in March, 1917, the steamships engaged in the trade were sailed in groups from four different assembly ports, viz.: Southend to Boulogne and Calais.
St.Helens to Havre.
Portland to Cherbourg.
Penzance to Brest.
Between Southend and Boulogne and Calais the protection was given by the vessels of the Dover Patrol in the course of their ordinary duties, but for the other three routes special escort forces were utilized, and daily convoys were the rule.
Owing to the great demand for coal in France, sailing vessels were also used, and sailed under convoy from several of the south-west ports.
A large organization was required to deal with the trade, and this was built up under the supervision of Captain Reginald G.H.Henderson, C.B., of the Anti-Submarine Division of the Naval Staff, working under Vice-Admiral (then Rear-Admiral) Sir Alexander Duff, head of the Division, in conference with the Commanders-in-Chief, Portsmouth and Plymouth, under whose direction and protection the convoys were run.

The immunity of this trade, carried out in the infested waters of the English Channel, from successful attack by submarines was extraordinary.
No doubt the small size of the vessels concerned and their comparatively shallow draught were a contributory cause to this immunity.

The figures for the period March to August, 1917, show that 8,825 vessels crossed the Channel under convoy, and that only fourteen were lost.
The history of the _Scandinavian and East Coast convoys_ dates back to the autumn of 1916, when heavy losses were being incurred amongst Scandinavian ships due to submarine attack.

Thus in October, 1916, the losses amongst Norwegian and Swedish ships by submarine attack were more than three times as great as the previous highest monthly losses.

Some fear existed that the neutral Scandinavian countries might refuse to run such risks and go to the extreme of prohibiting sailings.