Source: U.S. Hydrographic Chart #1262, 1912. W.S. Morison.
By the early 20th century, a global trade network supported by steamships was well established. Still, the range of steamships had limitations as the fuel used was coal. Refueling stages were required for long-distance trade, such as Cape Town, Pernambuco, Valparaiso, Honolulu, or Singapore. The Suez Canal was open in 1868, implying that the main trade route between Europe and the Far East was a linear sequence of intermediate locations; Port Said, Aden, Colombo, Singapore, and Hong Kong. Once the Panama Canal opened in 1914, transatlantic and transpacific routes were simplified.
By 1912, commercial sailship services were on the verge of disappearing and the only cost-effective routes were of extreme long distances such as New York – San Francisco (via Cape Horn) or Liverpool – Melbourne (via Cape of Good Hope). While steamship routes were direct and following when possible the great circle distance, sailship routes were configured to take advantage of dominant wind patterns. For instance, the Liverpool – Sydney sail route is shaped to take advantage of the “trade winds” (Westerlies).