The city government of Cambridge had no authority to assess the plaintiff, or any other person, for the expense of grading Charles Street and part of Fourth Street; the St. of 1853, c. 315, having been adjudged to be unconstitutional and void. Morse v. Stocker, 1 Allen, 150. And as no procesa was issued for the collection of the assessment, the plaintiff must be held to have paid it voluntarily when it was demanded of him, and therefore cannot recover it back. He was undei no compulsion, which the law recognizes as a ground for such recovery. See Boston & Sandwich Glass Co. v. Boston, 4 Met 181; Forbes v. Appleton, 5 Cush. 117, 118; Lee v. Templeton 13 Gray, 476.

Judgment for the defendants,