Period 6 element point of −38.83 °C and boiling point of 356.73 °C, mercury has one of the narrowest ranges of its liquid state of any metal. Mercury occurs in deposits throughout the world mostly as cinnabar (mercuric sulfide). The red pigment vermilion is mostly obtained by reduction from cinnabar. Cinnabar is highly toxic by ingestion or inhalation of the dust. Mercury poisoning can also result from exposure to water-soluble forms of mercury (such as mercuric chloride or methylmercury), inhalation of mercury vapor, or eating seafood contaminated with mercury. Mercury is used in thermometers, barometers, manometers, sphygmomanometers, float valves, mercury switches, and other
Ore dock built in 1865. By 1884, locomotives played a vital part in hauling ore from the mines to the docks. The pockets and chutes were filled using the hopper type ore cars. In 1889, the Duluth, South Shore and Atlantic Railway operated a dock with 284 pockets. The railroads also provided alternate transportation for people, goods and eventually, iron ore. The length and capacity of docks corresponded with the capacity of the ore freighters which they were designed to accommodate. As ore carriers increased in height and width, higher pocket openings were required and it was necessary to construct new docks