It was some time, however, before iron came into general use.

Ten years later, in 1832, Maudslay and Field built four iron vessels for the East India Company.

In the course of about twenty years, the use of iron became general, not only for ships of war, but for merchant ships plying to all parts of the world.
When ships began to be built of iron, it was found that they could be increased without limit, so long as coal, iron, machinery, and strong men full of skill and industry, were procurable.

The trade in shipbuilding returned to Britain, where iron ships are now made and exported in large numbers; the mercantile marine of this country exceeding in amount and tonnage that of all the other countries of the world put together.

The "wooden walls"[3] of England exist no more, for iron has superseded wood.