and the self-taught, practical man by giving him a working knowledge of the principles and methods, not only of his own particular trade, but of all other branches of the Building Industry as well. The various sections have been prepared especially for home study, each written by an acknowledged authority on the subject. The arrangement of matter is such as to carry the student forward by easy stages. Series of review questions are inserted in each volume, enabling the reader to test his knowledge and make it a permanent possession. The illustrations have been selected with unusual care to elucidate the text. The work will be found to cover many important topics on which little information has heretofore been available. This is especially apparent in such sections as those on Steel Construction; Reinforced Concrete Construction; Building Superintendence; Estimating; Contracts and Specifications, including the principles and methods of awarding and executing Government contracts; and Building Law. In conclusion, grateful acknowledgment is due the staff of authors and collaborators, without whose hearty co-operation this work would have been impossible. CARPENTRY VOLUME I Timber in Its Natural State: Classes of Trees, Growth, Wood Structure, Defects By Fred T. Hodgson and Morris Williams Definition of Terms-Setting-Out Stairs-Use of Pitch-Board-Well-Hole- Trimming-Straight Flights-Stairs: Dog-Legged, Platform, Winding, Circu- lar, Elliptical, Bullnose Steps, Open-Newel, with Curved Turns, Geometrical- Cylinder-Kerfing-Strengthening Stairs-Handrailing-Wreaths-Projection- Tangent System of Squaring Wreath Joints - Face-Mold-Bevels-Curves on Face Tongue-Blade-Back-Octagon Scale-Brace Rule-Board Measure- Nails and Screws-Hinges and Butts-Spring Butts-Double-Acting Butts- +For professional standing of authors, see list of Authors and Collaborators at CARPENTRY PART I INTRODUCTION The carpenter has always been a worker in wood and probably will always be so, unless we are so foolish as to neglect the newer art of Forestry to such an extent that in the course of time we have no wood wherein to work and with which to build and decorate our habitations. The building and the decoration of houses and other structures has always been the special contribution of the carpenter to the general welfare of the community, and this feature has distinguished him from other woodworkers such as carriage builders, shipbuilders, coopers, and makers of various implements. But whereas the carpenter formerly did all the work connected with the building or decoration of the structure, he now performs only a small part of it. At one time he was called upon to prepare the rough lumber for framing, erect the building, make the doors and windows together with their frames, and then make and put in place all the outside and inside finish, even including the furniture. In these days, however, factories are doing a great deal of this work, such as the manufacture of doors and window sash, interior finish, furniture, etc., and the lumber which was formerly prepared by hand is now sawed, cut, planed, molded, and even sandpapered by machinery, leaving for the carpenter the preparation of the framing of such buildings as are not large enough to be built of brick, stone, or steel, and the putting in place at the building of the exterior and interior finish which has previously been made ready so far as possible at the factory. The old-time joiner has given way to the modern cabinet maker or the factory woodworker, and his plane, saw, and chisel have been replaced by electrically-driven machinery of the planing mill and the door factory. Nevertheless, the principles upon which the art of carpentry is based have not changed, and we still use the formulas, and profit by the wisdom which has come down to us from our fathers. The carpenter has always found at hand his material provided by Nature, needing only to be cut down and shaped to suit his purposes. It is easily worked, beautiful in texture, and capable of being treated with paints, oils, and varnishes in such a way as to preserve it and at the same time give it a pleasing appearance. So suitable is wood for purposes of interior decoration that now when other materials such as sheet metal are substituted for it on account of their greater durability or their superiority as fire resistants, great pains are often taken to make these materials look like wood by the skillful use of paints and varnishes, and such good results have been obtained along this line, and the grain of the various kinds of wood has been so closely imitated, that one not accustomed to woodwork in a business way can hardly distinguish the real wood from the imitation. A knowledge of the characteristics of this material which plays so important a part in our lives and which is so plentiful, especially in the more recently settled parts of the earth, is sure to prove of advantage to all, and such knowledge is an absolute necessity to the carpenter, architect, or other user of wood. Unlike many of the other materials used in building, wood has life and has come into existence by a process known as growth, and these two facts have a very important bearing on the use of wood in construction, as they affect both its physical characteristics and its action after it has been put in place in a building. In order, therefore, to be able to make use of wood intelligently, it is necessary to know something about its mode of life, its method of growth, and the way in which it will act after it has been cut away from the tree, killed, so far as it is possible to kill it, by seasoning or drying, and then setting up in place. All woods are not the same in these respects; in fact, no two kinds of wood are exactly the same in structure, nor will they behave in the same way even under the same conditions, and this makes it necessary to select them very carefully for various purposes and for use in various places. While it is true that no two kinds of wood are exactly the same in structure, they still have some things in common. For example, all wood is a vegetable product, and all wood is built up in the same |