The growth in Cape Cod’s fishing industry early in the 19th century spawned other sea-related industries. One of the most important was the development of the saltworks. Salt was needed especially to preserve the cod and mackerel and other fish caught at such distant places as the Grand Banks. In colonial times, salt was obtained by boiling seawater in enormous iron pots that were set up near the beach, a technique that hastened the demise of the Cape’s forests. But as early as 1776, Captain John Sears of Dennis had experimented with making salt through evaporation of seawater in long shallow troughs. With a bushel of salt worth a dollar at the turn of the century, saltmaking became profitable and Cape Codders continued to improve their methods. They incorporated movable roofs on rails (right) to cover the troughs on cloudy or rainy days, windmills to pump seawater through hollow wooden pipes into the troughs, and an intricate system of reservoirs, falls, vats, and boiling rooms. The water went through three stages: evaporation, precipitation of lime, and crystallization of salt. Epsom salts came from boiling “bitter water,” the liquid remaining after the salt was crystallized. During the 1830s saltworks were a major industry in almost every Cape town, covering dozens of acres of beaches (background engraving). At their peak on Cape Cod, there were 442 saltworks producing more than 500,000 bushels of salt a year. By 1840, however, the opening up of large salt mines in the West, among other factors, signaled the beginning of the industry’s swift decline. Still, in the 1850s, Henry David Thoreau saw “saltworks scattered all along the shore, with their long rows of vats resting on piles driven into the marsh, their low, turtle-like roofs, and their ... windmills ... novel and interesting objects to an inlander.” ############################################# A Coastline Littered With Shipwrecks [Illustration: (Locations of Cape shipwrecks. The schooner “Messenger” grounded in Wellfleet. The fishing boat “Ulysses” in rough seas.)]