The experience of the author in teaching and in practice has led him to believe that no available book presents all structural subjects so concisely that they can be covered in the time usually allotted by technical schools. Moreover, the fundamental principles of shop practice and erection, which govern the designer at every step, are not clearly developed. These faults the author has attempted to correct, using only orthodox methods of presentation. This volume considers wooden structures and the fundamental principles of design in steel. Should this work receive recognition, it is intended to follow it by a second volume on the Design of Simple Structures, plate girders, viaducts, truss bridges, mill buildings, high Office buildings,. And standpipes, and a third on the Design of Advanced Structures, cantilever, movable, and suspension bridges and arches. It has been thought best for the present to omit the data usually found in handbooks. As a considerable portion of this treatise is original data, corrections and suggestions will be especially welcome. How ever, a great deal Of pains has been taken to eliminate errors.