In marine insurance. There is considerable analogy between ballast and dunnage. The former is used for trimming the ship, and bringing it down to a draft of water proper and safe for sailing. Dunnage is placed under the cargo to keep it from being wetted by water getting into the hold, or between the different parcels to keep them from bruising and injuring each other. Great Western Ins. Co. v. Thwing, 13 Wall. 674, 20 L. Ed. 607.