built with embers, and when the rocks are glowing hot, the embers are removed and the foods wrapped in ti, ginger or banana leaves are put into the pit, covered with wet leaves, mats and a layer of earth. Water may be added through a bamboo tube to create steam. The intense heat from the hot rocks cooked food thoroughly—the quantity of food for several days could be cooked at once, taken out and eaten as needed, and the cover replaced to keep the remainder warm. Sweet potatoes, taro, breadfruit and other vegetables were cooked in the imu, as well as fish. Saltwater eel was salted and dried before being put into the imu. Chickens, pigs and dogs were put into the imu with hot rocks inserted in the abdominal cavities. Men did all of the cooking, and food for women was cooked in a separate imu; afterwards men and women ate meals separately. The ancient practice of cooking with the imu continues to this day, for special occasions. Post-contact period In 1778, Captain James Cook arrived at the island of Niihau, leaving a ram goat, ewes, a boar, an English sow, and seeds for melons, pumpkins, and onions. In 1793, Captain George Vancouver brought the first cattle to the islands; longhorns from California were presented to King Kamehameha I. With no natural predators, the new cattle multiplied out of control; the king hired an American man named John Parker to capture and domesticate cattle. Many of the cattle were butchered and beef was introduced to Hawaiian cuisine. In 1813, pineapple was first cultivated in Honolulu by Don Francisco de Paula Marin, a Spanish botanist and advisor to King Kamehameha I. Although grape vines were introduced by Captain Vancouver around 1792, Marin is credited with the first Hawaiian vineyard in 1815 and planting the now rare Mission grape variety. Marin also brewed the first beer in 1812, and planted the first coffee crop in 1817, but his plantings failed. Marin, called "Manini" by the Hawaiians, experimented with planting oranges, limes, beans, cabbages, potatoes, peaches, melons, maize and lettuce. By the late 19th century, pineapple and sugarcane plantations owned and run by American settlers took over much of Hawaii's land, and these two crops became the most important sources of revenue for the Hawaiian economy. Ethnic foods As the plantations of the Big Five expanded, the demand for labor grew, so