of incorporation a provision that it should be of no avail or effect . . . . until a release and discharge of all the covenants of warranty made by this Commonwealth of any of the lands conveyed by said Commonwealth, lying at or near Lechmere's Point mentioned in this Act, shall be obtained from the person or persons who are legally authorized to make such release or discharge.
So also when John C. Jones, Loammi Baldwin, Aaron Dexter, Benjamin Weld, Joseph Coolidge, Jr., Benjamin Joy, Gorham Parsons, Jonathan Ingersoll, John Beach, Abijah Cheever, William B. Hutchins, Stephen Howard, and Andrew Craigie, with their associates, were incorporated, Feb. 27, 1807, with authority to erect Canal Bridge, familiarly called Craigie's Bridge, from the northwesterly end of Leverett street in Boston to the east end of Lechmere's Point, a similar provision was inserted that the act should be of no effect until a release and discharge of all the covenants of warranty contained in the deed of James