US Patent No. 7,861, granted December 24, 1850, to Samuel T. Thomas of Lowell and Edward Everett of Lawrence, Massachusetts, for an improved Jacquard loom for weaving figured fabrics. It replaces the knot-cord with horizontal harness bars that carry the mail cords (heddles), so the warp strain is more even in broad work and mountings can be changed more easily. It also describes a mechanism that rotates the pattern prism with a compound slide-rod and pawl movement. The document has three sheets of patent drawings, the specification and two claims.