Crag, a species of manure, consisting of the fragments of various marine shells, which abound on the greatest part of the cliffs, contiguous to the British coast. They are often found -40 or 50 feet higher than the level of the sea, and sometimes at a considerable distance from the shore.

This kind of manure has but lately been introduced into rural economy, and is not yet sufficiently known. The husbandman, indeed, who is so fortunate as to discover it near his farm, finds a treasure of which he cannot avail himself too soon ; as it will not only warm and meliorate a cold, wet, clayey soil, but also restore exhausted land, and render it equal to any, in richness and fertility. - See Manure.