Peter Plowman describes the liners and companies that traversed the Pacific. The main North American ports were San Francisco, Los Angeles and Vancouver. The Pacific Mail Steamship Company was the first to instigate regular operations, the route was then taken over by the Oceanic Steamship Company. This in turn became the Matson Line with its famous liners the Mariposa and the Monteray. Other companies were the Union Steam Ship Company (the Tahiti and Maunganui). The various company mergers and associations are covered (such as that of the Canadian Pacific Railway Company and the Union Steamship Company of New Zealand). Where liners were requisitioned in both World War 1 and World War 2, their history is recorded. (The Niagara was sunk by a mine, and her sister ship the Aorangi survived the war).