In 1870 the New Zealand and New South Wales Governments contracted for a mail service to San Francisco at a cost of £1,000 a month. The chartered steamers Rangatira and Balclutha, later replaced by the City of Melbourne and Wonga Wonga, connected at Honolulu with the American steamer Ajax. A year later an agreement was made with the Californian Line (Webb and Holladay) to run a fleet of four paddle steamers between Sydney and San Francisco, calling at New Zealand ports and Honolulu. These ships were the Nevada, Nebraska, and Dacotah, each of 2,145 tons, and Moses Taylor, of 1,354 tons. They were wooden vessels, with extensive passenger accommodation, and fitted with massive single-cylinder “beam” engines. In these, the piston rod was attached to one end of a huge horizontal beam pivoted at its centre on the upper deck and driving a 12 ft crank to turn the 30 ft paddles, giving the ship a speed of up to 17 knots. A series of misfortunes dogged the ships and the venture ended with the sailing of the Nebraska from Sydney in April 1873.

Then followed a service by the steamers Mongol, Tartar, and McGregor, later replaced by the Mikado, Cyphrenes, and City of Melbourne. After them came the American Pacific Mail Co. which employed several steamers in the service, including the Zealandia and Australia, both built by the Fairfield Co., of Glasgow. The American Pacific Mail Co. withdrew in 1885 and the San Francisco run was taken over jointly by Oceanic Co. of America and the Union Steam Ship Co. of New Zealand. The Oceanic Co. put on the Alameda and Mariposa and the Union Co. the new Mararoa which was replaced in 1890 by the Monowai and afterwards by the Arawa, chartered from the Shaw, Savill Line. The Moana, of 3,915 tons, specially built for the run, took over in 1897. But in 1900, when United States legislation forbade any but American ships to carry passengers and cargo between American ports, the Moana was transferred to the Vancouver mail service, that to San Francisco being maintained until 1907 by the Sierra, Sonoma, and Ventura.