A sailor and machinist work together to make the first steamship crossing of the Atlantic while the sailor falls in love with the machinist's daughter.
On a sailing ship Junius Smith (Vaughan Glaser) complains to Davie Gillespie (Douglas Fairbanks Jr.) his apples will rot. Captain Oliver (George Bancroft) has Gillespie order all men on deck; but Oliver won't shorten sail in a storm, and a sailors falls to his death. In Scotland a new steamship is launched, but Donald Fenton (David Torrence) prefers wind to coal and welcomes Oliver. Gillespie tells Mrs. Naughton she is a widow. Gillespie tells Fenton and Oliver he is leaving because they kill men for profits. Gillespie drinks with Oliver. John Shaw (Will Fyffe) says steam will cross the Atlantic, but Oliver laughs. Shaw says Oliver murdered two men, and they fight. Shaw tells Gillespie money is needed for steam. Gillespie goes home with drunk Shaw, whose daughter Mary Shaw (Margaret Lockwood) unlocks the door. Gillespie helps Shaw with his plans. Shaw shows him the foundry and says they could build his engine. Mary serves meals and says Shaw must not quit his job. Gillespie asks her to believe in her father's engine, but she asks Gillespie to go. Gillespie goes to Fenton, who rejects the idea. Gillespie tells Mary he is going to London.
Gillespie fails to persuade anyone and is hungry when Smith says he has a company for steamship navigation. Gillespie sends Mary money to bring Shaw to London. Mary tells Shaw, who quits his job. Shaw argues he should build his own engine rather than his old boss Malcolm Grant (Montagu Love). The engines are made by Shaw and Gillespie. Smith tells Gillespie they must be first to win the government subsidy. Grant gets a court order to stop them; but Gillespie argues successfully that Shaw was not working for Grant when they built the engine. Drunk Shaw starts a fire; Mary and Gillespie run in and rescue him.
In Scotland Gillespie tells Shaw they can cross the Atlantic in a steamer already built. Mary boards the ship and becomes a stewardess. Captain Gillespie tells Oliver he is replacing the extra sails with coal. Smith tells Gillespie that navy officer Lt. Roberts (Lester Matthews) must command with mail aboard. In 1838 the ship departs. Gillespie tells Roberts he replaced the extra sail, and they pass Oliver. Roberts lets Gillespie burn the spars. Gillespie asks Mary to marry, but a steam blow-out scalds Shaw. While Gillespie works to repair it, Oliver sees the distressed ship; but Gillespie persuades Roberts to decline help. Gillespie quells a mutiny and gets the steam working. The ship moves ahead and on to New York, where Cunard is interested. In the final scene ailing Shaw tells Gillespie to go on.
This drama shows the difficulty of getting support for
a new idea even when it is inevitable that it will eventually
surpass the old ways.