By the law, as it stood before the passing of the statutes of 1837, c. 229, and 1840, c. 35, any building beyond the line of low water mark, upon navigable tide waters, was an encroachment upon public right, and, if it obstructed navigation, was a public nuisance. The building, which is the subject of the alleged injury in the present case, is found by the jury to be below low water mark, and to be an obstruction to navigation. The plaintiff, being herself a *308wrong-doer, in having her building there, can maintain no action for the alleged damage. Arundel v. M’Culloch, 10 Mass. 70. The direction complained of was right, and the exceptions are overruled.

Judgment for the defendants.