Cinnabar means to gild silver and gold to objects) "the toxic properties of mercury were well known. It was dangerous to those who mined and processed cinnabar, it caused shaking, loss of sense, and death. Data suggest that mercury was retorted from cinnabar and the workers were exposed to the toxic mercury fumes." Overexposure to mercury, mercurialism, was seen as an occupational disease to the ancient Romans: "Mining in the Spanish cinnabar mines of Almadén, southwest of Madrid, was regarded as being akin to a death sentence due to the shortened life expectancy of the miners, who were slaves or convicts."
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