Merchant sailors were sometimes unemployed for long periods of time between voyages, and often lived in boarding houses near the piers while waiting for ships to come in and take on fresh crews. In such circumstances, many of them ran out of money, and so the innkeepers carried them on credit until they were hired for another voyage. When a sailor was booked on a ship, he was customarily advanced a month's wages, if needed, to pay off his boarding house debt. Once aboard ship, he worked for nothing but "salt horse" the first several weeks or so. Salt horse was the staple diet of early sailors and not tasty fare. Consisting of heavily salted, low quality beef, it was stringy and tough to chew. When the debt had been repaid, then the salt horse was said to be 'dead', for now the sailor could buy better food from the ship's stores, or bribe the cook or purser. This was a time for celebration among the crew. Usually, an effigy of a horse was constructed of shipboard odds and ends, set afire, and then thrown overboard amidst cheers and laughter. Another definition that is related to the first, is the fact that the "Horse Latitudes" lay towards the southern climates (Tropic of Cancer) near the Equator, which was roughly about a month's sail from England and Europe. Because of the doldrums (Lack of wind) in the area, ships were often becalmed for many days or weeks at a time, causing a water shortage. Livestock, especially horses, died first, or were simply killed and thrown overboard to save water. Their carcasses were often sighted by other ships traveling in this area, and so the region acquired that name. A sailor who had a debt to work off rejoiced at the sight of one of these floating bodies, knowing that he would soon be getting wages. In today's Navy, a "dead horse" refers to a debt to the government for advance pay.
