Passing quickly over the remainder of the earlier period, which the reader will find treated in full in the article Ship, he should notice that the sailing vessel came into use gradually for merchant use, but that galleys (propelled by oars) were long the only type for warships. There were some galleys even in the Spanish Armada of 1588. In the meantime the invention of gunpowder and the development of artillery brought about changes in size and in form, with a notable tendency to more masts and a greater spread of sail. The discoveries of the 15th and 16th centuries and especially the consequent expansion of trade in the 17th century, all tended to increase the size and efficiency of sailing ships. The end of the 18th and the beginning of the 19th century marked the highest point in the development of American sailing ships. “The Americans with their fast-sailing ‘clippers’ taught the English builders a lesson, showing that increased length in proportion to beam gave greater speed, while permitting the use of lighter rigging in proportion to tonnage, and the employment of smaller crews. The English shipyards were for a long time unequal to the task of producing vessels capable of competing with those of their American rivals, and their trade suffered accordingly. But after the repeal of the Navigation Laws in 1850, things improved and we find clippers from Aberdeen and the Clyde beginning to hold their own on the long voyages to China and elsewhere.”
The revolution in marine transportation by the introduction of steam is summed up by Sir Philip Watts as follows:
Before steam was applied to the propulsion of ships, the voyage from Great Britain to America lasted for some weeks; at the beginning of the 20th century the time had been reduced to about six days, and in 1910 the fastest vessels could do it in four and a half days. Similarly, the voyage to Australia, which took about thirteen weeks, had been reduced to thirty days or less. The fastest of the sailing tea-clippers required about three months to bring the early teas from China to Great Britain; in 1910 they were brought to London by the ordinary P. & O. service in five weeks. Atlantic liners now run between England and America which maintain speeds of 25 and 26 knots over the whole course, as compared with about 12 knots before the introduction of steam.
Iron Hulls
The introduction of iron for wood began about the same time as the substitution of steam for sails, and there was even more prejudice against it. This was due not merely to the sentiment attaching to the oaken timbers that typified “hearts of oak,” or to the “Wooden Walls of England.” In all seriousness it was objected that iron would not float! It was feared that iron bottoms would be more easily perforated when ships grounded; but this was found not to be the case when construction was careful. It was proved that fouling of iron bottoms from weeds and barnacles might be remedied by frequent cleaning and repainting. The most serious objection against iron was that it affected the compass; but in 1839 Sir G. B. Airy laid down rules for the correction of compass errors due to iron in construction. But even to-day wood is preferred for the construction of ships for scientific expeditions to the Polar regions where the slightest disturbance of the compass is to be avoided. Iron and steel (first used in shipbuilding to any extent in 1870–75) have three advantages over wooden ships: less weight; greater durability; greater ease in securing the necessary general and local strengths. But while iron was coming into use largely because it is more durable, there was a great increase in the durability of wooden ships, due to the improved knowledge of wood-preservation. At the end of the 18th century 15 or 20 years was the average life of a wooden ship; but there are several instances of ships built in the first decade of the 19th century—or even earlier—which were still in commission at the beginning of the 20th century.
Early Steamships
Full details are given in regard to the first ships used for canal and river navigation in Great Britain and the United States; the comparatively rapid adoption of steam vessels on the Irish and English channels; and the first steamships to make long trips—the American-built “Savannah” which crossed the Atlantic in 1819 in 25 days using steam only a part of the time, the “Enterprise” which went from London to Calcutta in 1825 in 103 days (64 under steam), the “Sirius,” the “Great Western,” etc. All these were propelled by paddle-wheels. Jet propulsion had been suggested by Benjamin Franklin in 1775 and was tried several times with some success. But the greater success of the screw-propeller, perfected by Colonel John Stevens and Captain John Ericsson, soon caused jet-propulsion to be abandoned. The screw-propeller made possible—and was quickly followed by—great improvements in engines; the gearing used with paddles was soon given up for direct-acting engines—compound about 1854, triple-expansion in 1874.
Statistics of shipping for all countries are given in tables and diagrams equivalent to 18 or 20 pages of this Guide.
A brief summary outline of the remainder of this article Ship is all that can be given here.
Merchant Vessels