So far as I can learn the first boat to be built of iron was launched in 1777 on the Foss river in Yorkshire. Later several lighters for canal work were built, one in particular being constructed near Birmingham in 1787. Less spectacular, but still highly important, was the introduction of iron for special uses in wooden vessels. This later grew into what came to be known as “composite” construction. The year 1818 is sometimes given as a definite date for the recognition of iron as an accepted ship-building material because in that year a lighter named the _Vulcan_ was built in the vicinity of Glasgow, but it is known that several iron hulls were built prior to that time. An iron steamboat named the _Aaron Manby_, after her builder, was operated for twenty years on the Seine after being built in England in 1821. She crossed the English Channel under her own power and made the trip from London to Paris. Still, however, there were many doubters, and not for more than twenty years was an iron ship of large size built. In 1843 the _Great Britain_, a ship of 3,600 tons, was built of iron, and this vessel was a notable step in the advancing art of ship-building. She was 322 feet long, 50 feet 6 inches broad, and was equipped to carry 260 passengers and more than a thousand tons of freight—surely no mean vessel, even to-day. This ship, as a matter of fact, proved a highly important affair, for she proved many things to the wiseacres of the day. I am indebted to E. Keble Chatterton, author of “The Mercantile Marine,” for his valuable story of her building and her adventures. So great and so unusual was this ship that, according to Mr. Chatterton, no contractor could be found who was willing to construct her. Consequently, the Great Western Steamship Company constructed her itself. She turned out, says Mr. Chatterton, to be “an awkward, ill-fated monstrosity,” but despite the fact that she did not prove that the combination of screw propeller and iron construction were successful, she did prove, after she ran ashore on the coast of Ireland, where she remained for eleven months exposed to the weather, before she was refloated, that an iron hull could withstand far more strenuous strains than any wooden hull could hold up under. This ship, furthermore, was divided into watertight compartments and was equipped with bilge keels, which are accepted to-day as an excellent method for lessening a ship’s rolling. By the time the American Civil War broke out in 1861, steam had made such definite strides that there were few to question its supremacy over sail.