English: This large oil painting by Arthur Lismer, a future member of the Group of Seven, depicts merchant ships forming up in Bedford Basin, near Halifax, Nova Scotia, for a trans-Atlantic convoy. Halifax was a vital naval base for merchant ships travelling from North America to bring food, supplies, and personnel to Britain and Europe. In 1917, the growing losses of these ships to German U-Boat (submarine) attacks led to the introduction of convoys, which banded together merchant ships and escorting warships. Convoys were effective, but required extensive organization to coordinate the arrivals, voyages, and departures of merchant ships and warships. The camouflage patterns depicted here, called "dazzle," were intended to help protect vessels at sea from U-Boat attack.