CHAPTER VI.
66. Introductory 70 67. First Cast-iron Arch 70 68. Early Timber Bridges in America 71 69. Town Lattice Bridge 72 70. Howe Truss 74 71. Pratt Truss 76 72. Squire Whipple’s Work 77 73. Character of Work of Early Builders 77
66. Introductory 70 67. First Cast-iron Arch 70 68. Early Timber Bridges in America 71 69. Town Lattice Bridge 72 70. Howe Truss 74 71. Pratt Truss 76 72. Squire Whipple’s Work 77 73. Character of Work of Early Builders 77