ALLUVION. That increase of the earth on a shore or bank of a river by the force of the water, as by a current or by waves, which is so gradual that no one can judge how much is added at each moment of time. Inst. 1. 2, t. 1, 20; 3 Barnew. & C. 91; Code Civil Annote, n. 556.
The proprietor of the bank increased by alluvion is entitled to the addition, this being regarded as the equivalent for the loss he may sustain from the breaking-in or en croachment of the waters upon his land. 1 Washburn, Real Prop. 451; 2 Md. Ch. Dec. 485 ; 1 Gill & J. Md. 249 ; 4 Pick. Mass. 273 ; 17 id. 41; 1 Hawks' Tenn. 56; 6 Mart. La. 19 ; 11 Ohio, 311 ; 10 Pet. 662; 5 Wheat. 380. The increase is to be divided among riparian proprietors by the following rule: measure the whole extent of their ancient line on the river, and ascertain how many feet each pro prietor owned on this line; divide the newly formed river-line into equal parts, and ap propriate to each proprietor as many of these parts as he owned feet on the old line, and then draw lines from the points at which the proprietors respectively bounded on the old to the points thus determined as the points of division on the newly-formed shore. In
applying this rule, allowance must be made for projections and indentations in the old line. 17 Pick. Mass. 41; 9 Me. 44; 17 Vt. 387. Where the increase is instantaneous, it belongs to the sovereign, upon the ground that it was a part of the bed of the river of which he was proprietor. 17 Ala. 9; 2 Black stone, Comm. 269.
Seaweed which is thrown upon a beach, as partaking of the nature of alluvion, be longs to the owner of the beach. 7 Metc. Mass. 373; 2 Johns. N. Y. 322; 3 Barnew. & Ad. 967. But sea-weed below low-water mark on the bed of a navigable river belongs to the public. 9 Conn. 38.
Alluvion differs from avulsion in this, that the latter is sudden and perceptible. See AVULSION. And see 2 Ld. Raym. 737 ; Phear, Rights of Water, 12 ; 1 Swift, Dig. 111 ; Cooper, inst. 1. 2, t. 1; Angell, Watercourses, 53 et seq.; Phillimore, Int. Law, 255; Schultes, Aq. Rights, 116; 2 Am. Law Jour. 282, 293; Angell, Tide Waters, 249 ; Inst. 2. 1. 20; Dig. 41. 1. 7; id. 39.2. 9; id. 6. 1. 23; id. 41. 1. 5; 1 Bouvier, Inst. 74.