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Again, a knowledge of the graphic art is now demanded of all who are in any way connected with mechanical constructions of any kind, and no one can now hope to obtain any position of trust that an engineer fills, who has not acquired the power of correct drawing. It was long a fallacy with many, that draughtsmen were born, not made ; that although a youth, or a man, may be taught to write or copy letters the law did not hold good as regarded drawing. This fallacy has happily gone the way of many others, and it is now held that those who will give to the study of Drawing the necessary concentration of thought, coupled with persistent effort, will undoubtedly attain its mastery and achieve success. FIRST PRINCIPLES OP MECHANICAL AND ENGINEERING DRAWING CHAPTER I THE TOOLS AND MATERIALS REQUIRED BY THE STUDENT 1. Drawing-Board. As all drawings of Mechanical and Engineering subjects are made on flat surfaces, and as the most suitable material on which such drawings may be made is paper, the first requisite of the student is a drawing-board, on which to lay or stretch the paper. The board should be made of well-seasoned pine, of a convenient size say 23 in. by 17 in., which will take half-a-sheet of Imperial paper, leaving J- in. margin all round J in. in thickness, and fitted at the back, at right angles to its longest side, with a couple of hardwood battens, about 2 in. wide and J in. thick ; the use of these battens being to keep the board from casting or winding, and to allow of its expansion or contraction through changes of temperature. This latter