Four designs for rebuilding Bristol Bridge. [electronic resource] : (humbly inscrib'd to the Gentlemen appointed Commissioners for building the same) Wherein are Explained I. A Design of three Semicircular Arches on the Old Foundation. II. A Design of three Eliptical Arches (also) on the old Foundation, chiefly calculated to save Expence, &c. III. A Design of five Segment Arches on a new Foundation. IV. A Design of an Arch 130 Feet Cord, and Altitude 29. V. The Properties of the different Quarry Stones used in England, and which are most fit for a Work of this Kind. VI. The Result of a Calculation made on the obstructed Water, occasioned by the great Bulk of the old Pillars, and the Advantage gained by rebuilding the Bridge according to any one of these Designs. Vii. Of Models and their appendant Machines, necessary for building this Bridge, according to the 1st, 2d, and 3d Design. As also a short description of the method and size of the materials (propos'd) to be used in the Course of this Work. By James Bridges, Architect.