By the early 1900s, steamships already provided the primary means to transport people and goods across oceans. Steam created by giant vats of boiling water provided consistent power, making ocean crossings predictable as ships didn't depend on wind for propulsion. But by the start of the 20th century, the adaptation of turbines to steam engines on ships greatly improved their speed and fuel efficiency. The use of steam turbines shaved two days off the average transatlantic crossing.

Built for Speed

The first passenger vessel powered by steam turbines was the Mauretania, a British liner built in 1907 by the Cunard Steamship Company. Repeatedly out-built by competitors, Cunard secured loans from the British government to build the biggest and fastest steamship in existence. The Mauretania's quadruple turbines produced 70,000 horsepower and propelled the ship to speeds in excess of 30 miles per hour. Fueling the ship required a boiler room crew of more than 300 men, working in shifts to feed more than 1,000 tons of coal per day into the fires that heated the boilers. All the work and investment paid off in September 1909 when the Mauretania captured the Blue Riband, an award for the fastest crossing of the Atlantic Ocean. The ship's record stood for two decades.

Fueling Immigration

In the late 1800s and early 1900s, more than 90 percent of immigrants to the U.S. arrived on steamships from all over the world. When Cunard launched the Campania and the Lucania in 1893, they were the largest transatlantic passenger vessels of the time. Each ship was capable of carrying as many as 2,000 passengers -- half of them in third-class steerage spaces. In the Pacific, Japanese and Chinese laborers boarded steamships to Hawaii to work on sugar plantations. Steamships gained fame for the opulence and high style of the first-class cabins, designed to appeal to wealthy transatlantic tourism. Immigrant trade, however, continued to be the main source of income for most passenger liners in the early 1900s. As shipping lines scrambled to meet the emigration demand, room to carry more passengers led to pressure to build even larger ships.

Transatlantic Elegance

Leisure travel to Europe on steamships was a mark of status and prestige for wealthy Americans in the early 1900s. Shipbuilders and designers competed with one another to create extravagant luxury on board that matched the finest restaurants and hotels on land. For example, Cunard outfitted its Lusitania and Mauretania with palm courts, orchestras, telephones and daily newspapers printed at sea from news briefs received via radio transmissions. These ships were sources of national pride and floating works of art. For example, as many as 28 different woods were used to decorate the opulent spaces of the Mauretania.

Disaster on the High Seas

While steam-powered vessels were safer than sailing ships, they were not immune from disaster. Heralded as a triumph of technology over the forces of nature, the White Star Line famously proclaimed its flagship Titanic was practically unsinkable. However, the ship struck an iceberg on April 14, 1912, sinking in less than three hours. More than 1,500 passengers and crew lost their lives. Due in part to overconfidence in the ship's safety, the Titanic only carried lifeboats for approximately one-third of the passengers aboard. Other steamships met disastrous ends as well. For example, the Lusitania was sunk by a German U-boat in 1915, resulting in the loss of 1,198 lives.