The Airmetal Chain at Amethyst Cove

Amethyst Cove is, except for the harbor caverns of Cliffport, perhaps the most naturally sheltered harbor for seagoing vessels in all of Cartyrion. But when the Dwarves established a seaport on this harbor, they decided that it needed further protections. At the outbreak of the Great Strife, they began construction of the most formidable of these: the Amethyst Gate, and the massive chain that would prevent any undesirable ships from entering the harbor.

Amethyst Gate

Long before the Great Strife began, the Dwarves had deepened one channel through the reefs to ensure a safe passage for ships into and out of their harbor at Amethyst Cove. But with the onset of hostilities, they decided that channel needed a defense. To this end, they devised a plan to place a gate of sorts across the channel.

Two large, circular stone towers were first erected. One of these was placed at the foot of Amethyst Tor, which marked the location of the channel for all approaching ships from the Great Sea. The second tower was erected atop the reefs across the channel from the first. Outwardly, these towers were platforms from which the defenders could fire ballistae and catapults at enemy ships attempting to enter the harbor.

Technology

Airmetal Seachain

Materials

Dwarven Airmetal (aluminum)
w/ Dwarven Bluemetal (zinc) plating

Their true purpose, though, was to house the winch mechanisms for drawing up and letting down a massive chain that stretched between the two towers at just below sea level. When drawn up tight, the chain would prevent any vessel with a draft of more than a foot from passing the towers. Friendly ships could come and go with the chaind relaxed and dropped to the channel floor.

The Airmetal Chain

The genius in the technology was in the crafting of the chain itself. Dwarves build things to last, and they knew that iron or steel would rust in the salt water of the sea. Furthermore, a chain made from iron or steel would be quite heavy, and therefore quite difficult to winch up and down quickly as needed.

Their solution was to use a metal first discovered deep in the mines of the Ironhills Delve, but subsequently in other Delves as well. This metal was found in ores that were difficult to process, but the refined product was a metal that was soft and malleable enough to be shaped in a variety of ways. Silvery in color at first, it would soon take on a dull matte finish, but utherwise seemed rust-proof. But the most amazing property was the weight of the metal - less than half that of iron or steel - even lighter than elven steel (mithril).

To form the Amethyst Gate chain, they forged and welded links that were 10ft (3m) long and 7ft (2m) wide, with the metal of the links being 20in (.5m) thick. To guarantee against corrosion in the sea, they plated each link with Bluemetal, another product discovered in their mines over the years. Dwarves had long mixed this metal with copper to make brass, and had learned how to use elemental lightning to apply it as plating to iron or airmetal to guard against corrosion.

The ends of the chain were affixed to the winches with heavy cables fashioned of spidersilk; these cables were then wound around windlasses in the base of each tower. It took twenty Dwarves turning each winch to raise the chain to its blocking position.

Footnotes

Dwarven Metals from A to Z

Many metals we are familiar with in our real world have equivalents in Cartyrion, though the names are different. Iron, steel, copper, silver, gold, platinum, brass, bronze and pewter are familar, but others may not be:

Airmetal is Aluminum for the US folks, and Aluminium for the rest of the world. It is called Airmetal because it is so lightweight. It is usually used in pure form, but can be electroplated (with magical lightning) using Bluemetal to prevent corrosion in harsh environments.

Bluemetal is Zinc, so named because of its bluish-white tinge in pure form. Rarely used in pure form, it is essential for corrosion-resistant electroplating and for making brass.

Silverstel is Chromium; it is used almost exclusively in alloys such as Elven Steel to impart it mirrorlike luster to finished materials.

Watermetal is Tungsten, so named because of its extremely high melting point. (Scholars believe it must be heavily infused with Water Energy to be able to resist Fire so well). While possible to use in pure form by the most highly skilled artisans, its most common use is to be alloyed with steel to make Dwarven Steel (Adamantite).

Whitesteel is Titanium; it can be used as a pure metal, but is more often alloyed with silversteel and steel to form Elven Steel (Mithril).

Credits

Page Banner Orc Warrior Image by Yuri_B from Pixabay
Page Banner Sailing Ship Image by GLady from Pixabay