Definitions
1.NounCoal from the sea: mineral coal that washes up from the sea onto beaches.
2.NounCoal from across the sea: mineral coal, as opposed to charcoal, in a time and place in which the former arrived by ship and the latter arrived overland (such as London in Elizabethan times).
3.NounCoal to be used at sea: a certain class of mineral coal, especially suitable for the steam engines of ships at sea and locomotives.
4.NounSuch coal used in foundry practice, intermixed with foundry sand or applied in a layer on its face, to modify the behavior of the molten metal.