CHAPTER IV.
THE INTRODUCTION OF THE CONVOY SYSTEM The question of the introduction of convoys for the protection of merchant ships was under consideration at various times during the war.
The system had been employed during the old wars and had proved its value in the case of attack by vessels on the surface, and it was natural that thoughts should be directed towards its reintroduction when the submarine campaign developed.

There is one inherent disadvantage in this system which cannot be overcome, although it can be mitigated by careful organization, viz.

the delay involved.

Delay means, of course, a loss of carrying-power, and when tonnage is already short any proposal which must reduce its efficiency has to be very carefully examined.

The delay of the convoy system is due to two causes, (a) because the speed of the convoy must necessarily be fixed by the speed of the slowest ship, and (b) the fact that the arrival of a large number of ships at one time may cause congestion and consequent delay at the port of unloading.