The Birth of Leviathans: How the Ships of the Line were Built

The vessels of the Royal Navy were built in various dockyards across Britain. The designs were produced by the master-shipwrights of the dockyard. They usually worked in their studio known as the “mould-loft”, situated not far from the dry docks and building slips. On the floor of these mould-lofts, the plan of the ship was drawn to a 1:1 scale. On the high walls, the side elevations were then drawn in chalk, from the keel to the top of the poop railings. When the master shipwright was satisfied with the plan, he ordered the timber to be cut according to the lines of the plan in the mould-loft.

The most important yards were at Chatham, Deptford, Woolwich, and Plymouth. While the smaller ships were built directly on the building slips or launches, which were directly connected to the riverside, the larger vessels were constructed in the dry docks.

The ship’s keel (or backbone) was then “laid down” upon oak blocks. In Nelson’s day, the backbone was usually made of thick elm timbers. The timbers were “scarfed together,” meaning they were bolted and clinched at the sides. Beneath the keel was a “false keel” made of elm, designed to protect the actual keel if the ship grounded. Next, the hull of the ship was built upon the keel. The wood used was mostly oak from England, with important sources being the Forest of Dean in Gloucestershire and the New Forest in Hampshire. After the trees were cut down, the navy had to wait one year before they could use them, as the oak had to be seasoned before being employed in construction. Upon arrival at the dockyard, the oak timbers were stored in various sheds, where they remained for several months to season. Since a ship’s hull is not rectangular, the oak had to be curved to fit the frame. To achieve this, the timbers were pickled or boiled in a kiln for many hours, allowing the builders to bend the oak into shape.

Before planking the hull’s frame, the skeleton was left exposed to the open air for twelve months, as it was believed this would further season and strengthen the structure. However, it was later discovered that this practice actually caused decay before the ship’s hull was even planked. Ships built in this way typically had a lifespan of only 8 to 9 years, unless properly cared for. The timbers were secured to the uprights of the frame using long wooden pins known as treenails. Although treenails were considered unreliable, dockyards continued to use them out of tradition and to save costs. However, they often shrank after the ship was launched, allowing water to seep into the hull. The soaked wood quickly began to develop fungus as water penetrated its fibers. Once established, dry rot and fungus spread rapidly throughout the ship.

For a third-rate ship of the line, approximately 2,000 oak trees were required, half of which had to be imported. English oak was preferred for its superior quality. Once the hull was planked, the ship was caulked to make it watertight. The Teredo navalis, or shipworm, was the navy’s greatest enemy (after the French), as this species of saltwater clam relentlessly ate through a ship’s wood year after year. In 1758, an experiment was conducted on the 32-gun frigate HMS Alarm. The Admiralty ordered her underwater hull to be sheathed with thin sheets of copper. The copper proved impervious to shipworm and significantly reduced the formation of barnacles and other fouling organisms that would have otherwise slowed the ship over time. However, the experiment was not entirely successful at first, as the copper corroded the iron bolts. This issue was later resolved by adding a thin layer of wood between the copper sheets and the hull, preventing contact between the bolts and the copper. By the late 18th century, copper sheathing had become standard practice in both the navy and the merchant fleet.

After the ship was launched, she was brought alongside a “sheer hulk,” an old, decommissioned ship of the line equipped with a single mast functioning as a crane. The sheer hulk was used to fit the bowsprit and the lower masts onto the new vessel. The masts were sourced from the dockyard’s mast pond, essentially a large vat of pickle used for storing them. Afterwards, the rigging, brought from the rigging loft, was fitted to the ship. The lower rigging was set up by the master rigger, aided by the marines and standing officers. Shrouds and stays were made of hempen rope, tarred on the outside. After the lower rigging, the jib boom and the topmasts were fitted and rigged. Finally, the flying jib boom, topgallant masts, and royal masts were completed. The standing rigging was now finished.

The next step in fitting the rigging was attaching the yards to the masts, to which the square sails were connected. These yards were usually made of fir. Square-rigged sails were not the only ones fitted to a warship. There was also the spanker for increased maneuverability, pointing fore and aft, the stay-sails between the masts, the studding sails at the extremities of the yards, and the triangular jibs between the bowsprit and the foremast. Spare masts, spars, sails, and rigging were kept in stock at the yard.

It is said that the French were actually the superior shipbuilders, being much more imaginative and innovative. Be that as it may, in the end, it was the tars and their training belowdecks, as well as the genius and boldness of the Royal Navy’s leaders, that made all the difference and ensured Britain became master of the seas by the end of the Napoleonic Wars.

Olivier Goossens