PREFACE. AT the suggestion of the publishers this work was undertaken to form one of their series of Dictionaries and Cyclopædias. In this view, it has been the intention to make it a complete course of instruction and book of reference to the mechanic, architect and engineer, It has not therefore been confined to the explanation and illustration of the methods of projection, and the delineation of objects which might serve as copies to the draughtsman, matters of essential importance for the correct and intelligible representation of every form; but it contains the means of determining the amount and direction of strains, to which different parts of a machine or structure may be subjected, and the rules for disposing and proportioning of the material employed, to the safe and permanent resistance of those strains, with practical applications of the same. Thus while it supplies numerous illustrations in every department for the mere copyist, it also affords suggestions and aids to the mechanic in the execution of new designs. And although the arranging and properly proportioning alone of material in a suitable direction and adequately to the resistance of the strains to which it might be exposed, would produce a structure sufficient in point of strength for the purposes for which it is intended, yet as in many cases the disposition of the material may be applied not only practically, but also artistically, and adapted to the reception of ornament, under the head of Architectural Drawing the general characteristics of various styles have been treated of, and illustrated, with brief remarks on proportion and the application of color. Within the last few years both here and abroad, a number of works have been published on "Practical Drawing," but no one work has illustrated all departments of the subject. In the mechanical, the works of M. Le Brun and M. M. Armengaud are the standard which have been made the basis of two English works, "The practical Draughtsman's Book of Industrial Design" and the "Engineer's and Machinist's Drawing Book." From the latter of these works we have drawn most of our chapters on Geometrical and Mechanical Drawing, and Shades and Shadows. In neither the French nor the English works has the science of architectural construction and drawing been adequately illustrated, nor has Topographical Drawing been treated of. In these two departments a varied selection has been made from the best authorities. In the Architectural, Ferguson and Garbett have been the most consulted; in the Topographical, Williams, Gillespie, Smith and Frome. The work will be found quite fully illustrated, and the drawings and engravings have been carefully executed, mostly under the supervision of Mr. H. Grassau. Like most cyclopædias, this work claims for its articles but little of novelty or originality; the intention of the compiler was to collect within moderate compass as much valuable matter as possible, in practical Drawing and Design; and to this purpose he brings the experience of series of years in each of the departments treated. Practically, he has had means of knowing the necessities of the trade and of the profession, and trusts that the selection now made will be found useful for the purposes for which it was intended.-W. TABLE OF CONTENTS. GEOMETRICAL DEFINITIONS OF TECHNICALITIES. Point defined, 1; given points defined, 1; lines defined, 1; parallel lines defined, 1; horizontal lines defined, 1; superficies de scribed, 1; solids described, 1; lines vertical defined, 1; inclined lines defined, 1 ; angle defined, 2; obtuse angle defined, 2; acute angle defined, 2; triangle defined, 2; equilateral triangle, 2; isosceles triangle, 2; scalene triangle, 2; quadrilateral figure defined, 2; parallelogram described, 2; square described, 3; rectangle described, 3; rhombus described, 3; trapezium described, 3; polygons described, 3; regular polygons described, 3; circle described, 3; concentric, 3; eccentric, 3; arc defined, 3; sector defined, 3; chord defined, 3; circle, its circumference divided, 4; ellipse defined, 4; parabola described, 4; hyperbola described, 5; cycloid described, 5; epicycloid described, 5; hypocycloid described, 5. OF SOLIDS. Prism described, 5; pyramid described, 5; sphere defined, 6; cylinder defined, 6; cone defined, 6; tetrahedron described, 6; hexahedron described, 6; octahedron described, 6; dodecahedron described, 6; isosahedron described, 6. DRAWING INSTRUMENTS. Ruler common, 7; how made, 7; uses, 7; parallel ruler, 10; how made, 10; triangle wooden, 7; how made, 7; uses, 8; square, the T, 9; how made, 9; sweeps or variable curves, 10; compasses or dividers, 11; hair dividers, 12; dividers with mov able points, 12; bow dividers, 13; spring dividers, 13; drawing pen, 14; dotting point, 15; drawing pins, 15. Scales, 16. On the selection of the scale, 17 ; diagonal scales, 18; plotting scales and rulers, 19; application of the protractor, 19; Vernier's scale, 19; general rule for Vernier's scale, 20; to set off an angle, 21; use of the lines of sines, secants, tangents and semitangents, 21; the line of rhombs, 21; the line of longitudes, 21; the sector, 22; plain scales on the sector, 22; sectoral double scales, 22; the line of lines, 23; to divide a given line into eight equal parts, 23; to form any required scale of equal parts, 23; example, 23; to construct a scale of feet and inches representing various dimensions, 23; examples, 23; line of chords, 23; line of polygons, 24; line of sines, tangents, &c., 25; examples, 25; Marquois scales, 26; example, 26. Triangular Compasses, 27. Uses, 27; wholes and halves, 28; proportional compasses, 28; beam compasses, 29; method of use, 29; portable or turn-in compasses, 30; tubular compasses of Brunel, 31; large screw dividers, 31; circular protractor, 31; use, 32; pentagraph, 33; method of use, 34; camera lucida, 35; drawing table and board, 35. Drawing paper, 35; tracing paper, 36; smooth glue, 36; damp stretching, 37; mounting paper and drawings, 38; varnishing, 38; management of instruments, 39. GEOMETRICAL PROBLEMS. To draw straight lines through given points, 42; how lines are divided in drawing, 42; to set off a given distance, 43; to divide a given line, 43-44-45; to draw a perpendic- ular to a straight line, 45; various methods, 45-46; to draw a straight line parallel to a given line, 47; to draw a parallel through a given point, 47; to construct an angle equal to a given angle, 48; to divide an an- gle, 48; to bisect an angle, 49; to describe an arc through given points with a given radius, 49; to find the centre of a given circle, 49; to describe a circle through three given points, 50; methods, 50; to draw a tangent to a circle from a given point in the circumference, 51; to draw a tangent to a circle from a point without it, 51; to describe a circle from a given point to touch a given circle, 52; to draw tangents to two given circles, 52; methods, 52; between two inclined lines to draw a series of circles touching each other and those lines, 53; between two inclined lines to draw a circu- lar segment to fill up the angle and touch- ing the line, 53; to fill up the angle of a straight line and a circle with a circular arch, &c., 54; to fill up the angle of a straight line and a circle with a circular arch, and to join the circle at a given point, 54; to describe a circular arc joining two circles, and to touch one of them at a given point, 54; to find an arc tangent to a given point on a straight line, 55; to connect two parallel lines by a reversed curve com- posed of two arcs of equal radius, 55; to join two given points in two given parallel lines, by a reversed curve of two equal arcs, &c., 55. Problems on Circles and Rectilinear Figures, 56. To construct a triangle upon a given straight line, the length of the two sides being given, 56; to construct a square on a given line, 57; to construct a parallelogram | on a given line, 57; to describe a circle about a parallelogram, 58; to inscribe a circle in a triangle, 58; to inscribe a square in a circle, 58; to inscribe a circle in a square, 59; to inscribe a pentagon in a circle, 59; to inscribe a hexagon in a circle, 59; to describe a hexagon about a circle, 60; to construct a regular octagon on a given straight line, 60; to convert a square into a regular octagon, 60; to inscribe an octa- gon in a circle, 61; to inscribe a circle within a polygon, 61; to describe a regu- lar octagon about a circle, 61; to describe a circle without a polygon, 61; table of T square and triangle in the construction of some of the foregoing problems, 63. Simple application of regular figures, 65. To cover a surface with equilateral triangles, hexagons and lozenges, 65; to cover a sur- face with octagons and squares, 65. Problems on proportional lines and equiva- lent figures, 66. To divide a straight line into two parts proportional to two given lines, 66; to divide a straight line into any number of parts of given proportions, 66; to find a fourth proportional to three given lines, 67; to find a mean proportional to two, 67; to construct a triangle equal in area to a given rectangle, 67; to construct a square equal to a given rectangle, 67; to construct a triangle equivalent to any reg- Problems on the Ellipse, the Parabola, the Hyperbola, the Cycloid and the Epicycloid, 68. To describe an ellipse, the length and breadth being given, 68; methods, 68-69; to draw a tangent to an ellipse through a given point in the curve, 70; to draw a tan- gent to an ellipse from a given point with- out the curve, 70; to describe an ellipse approximately by means of circular arcs, 71. To construct a parabola when the focus and directrix are given, 72; methods, 72; to construct a parabola when other points are given, 73; to draw a tangent to a given To describe an hyperbola, 74; to draw a tan- gent to any point of an hyperbola, 74. To describe a cycloid, 75; to describe an epi- Arithmetical and mechanical drawing de- scribed, 80. Shade Lines, 83; outline draw- ings, 83; French system of shading, 85. Projections of simple bodies, 85. Projection of an hexagonal pyramid, 85; projection of an hexagonal pyramid with the base in an in- clined position, &c., 86; to find the hori- zontal projection of a transverse section of said pyramid, 87; to find the horizontal projection of a transverse section of a reg- Projections of a Prism, 88. To represent in plan and elevation a six-sided prism in an upright position, 88; to form the projec- tions of the same prism, 88; the projections Construction of the Conic Sections, 90 ; to find Penetrations of cylinders, prisms, spheres and cones, 97. To delineate the lines of penetration of a sphere and a regular hexagonal prism, &c., 97; to delineate the lines of penetration of a cylinder and a sphere, the centre of the sphere without the axis of the cylinder, 98; to delineate the lines of penetration of a truncated cone and a prism, 98; to de- DEVELOPMENT OF SURFACES. To develope the surface of a cylinder formed by the intersection of another cylinder, 102; to develope the surface of a frustum of a MECHANICS. Force defined, 105; direction of, 105; lines formed by three forces, 106; forces repre- sented by the sides of a polygon, 107; par- allel forces, 108; centre of gravity, 109 ; to The Mechanical powers, 110; the incline, 110. To find the power that will support a given weight, 111; to find the weight that will be sustained by a known power, 111; to find the height of an inclined plane neces- sary to sustain a given weight, 111; the wedge, 112; the screw, 112; to calculate the power imparted to a screw, 112; to find the weight raised, 112. Levers, 112; levers first class, 112; levers second class, 113; levers third class, 113; to find the position of the fulcrum to support a given weight &c., 113; to find the weight &c., 113; to find the power &c., 113. The 115; experiments on friction by M. Morin, detrusion, 128; torsion, 128; examples, 129. Mechanical work or effect, 130; explained, 130; unit of, 130; motors, 131; circum- stances demanding attention on the appli- cation of strength, 131; average amount of mechanical effect produced by men and animals in different applications, 131; ex- ample, 132; water power, 133; example, one inch of water, 135; table showing the weights, evaporative powers per weight, and Shafting, 137; described, 137; diameters of the journals of water-wheels and other shafts for heavy work, 138; description of cuts, 138-139; the torsal strain on a shaft, 140. Table of diameters for shaft journals with 141. Bearings or supports for the journals of shafts, 142; for upright shafts, 142; explanation of cuts, 143-144; pillow, plumber block or standard and hangers, 145. Projections of a standard, 146; ex- planation of cuts, 147-148; couplings, 148; face couplings, 148; explanation of cuts, 149; box or sleeve coupling, 150; horned coupling, 150; slide or clutch coupling, 151; friction cone coupling, 152; pulleys, 152; pulleys, cast iron, 153; explanation of cuts, 153; drums, 154; cone pulleys 154. Table of strain on the belt by Morin, 155; application of the table, 155; fast and |