A Text Book of Geometrical Drawing: For the Use of Mechanics and Schools, in which the Definitions and Rules of Geometry are Familiarly Explained ... With Illustrations for Drawing Plans, Sections and Elevations of Buildings and Machinery: an Introduction to Isometrical Drawing: a Course of Linear Perspective and Shadows: an Essay of the Theory of Color, and Its Application to Architectural and Mechanical Drawings. The Whole Illustrated with Fifty-six Steel Plates |
Common terms and phrases
angle of 45 applied arch axis Bisect blue breadth called centre for describing chords circle circumference complementary color cone corners cube Cycloid cylinder CYMA describe the arc diagram diameter dividers Dodecagon dotted lines draw a diagonal draw a line draw lines draw rays edge elevation ellipsis erect perpendiculars feet FIGURE fillet foot front frustrum given height hexagon horizontal line hues HYPERBOLA inches India ink ISOMETRICAL length LIBRA lines drawn lines parallel middle visual ray Minifie NOTE number of equal object ovolo parabola parallel ruler parallelogram perspective plane PLATE point of distance point of sight points of division points of intersection polygon primary colors PROBLEM projection Prussian blue pyramid radius equal rays of light right angles right line scale semicircle shade shadow shew shewn sides spectator square surface tangent Tetragon tint triangle vanishing point vertical viewed voussoirs wall yellow
Popular passages
Page 12 - A Segment is any part of a circle bounded by an arc and its chord. 51. A Semicircle is half the circle, or a segment cut off by a diameter. The half circumference is sometimes called the Semicircle. 52. A...
Page 45 - CVIIf any Prism be cut by a Plane Parallel to its Base, the Section will be equal and Like to the Base. LET AG be any prism, and...
Page 16 - The square of the hypothenuse of a right angled triangle is equal to the sum of the squares of both the other sides. 4th. The square of a number is the product of that number multiplied by itself.
Page 9 - A right-angled triangle (Fig. 24) is any triangle having one right angle. The side opposite the right angle is called the hypotenuse.
Page 128 - When a yellow colour is communicated to dull and coarse surfaces, such as common cloth, felt, or the like, on which it does not appear with full energy, the disagreeable effect alluded to is apparent. By a slight and scarcely perceptible change, the beautiful impression of fire and gold is transformed into one not undeserving the epithet foul ; and the colour of honour and joy reversed to that of ignominy and aversion. To this impression the yellow hats of bankrupts and the yellow circles on the...
Page 43 - E and F are FOCI. 5th. In the foci, stick two pins, then pass a string around them, and tie the ends together at C. 6th. Place the point of a pencil at C, and keeping the string tight, pass it around and describe the curve. NOTE. — The sum of all lines drawn from the foci, to any point in the curve, is always constant and equal to the major axis : thus, the length of the lines E. R, and F. R, added together, is equal to the length of E. C, and F. C, added together, or to two lines drawn from E...
Page 12 - A QUADRANT is a sector whose area is equal to one-fourth of the circle, as fig. 5; the arc D. E being equal to one-fourth of the whole circumference, and the radii at right angles to each other. 12. A DEGREE. — The circumference of a circle is considered as divided into 360 equal parts called DEGREES, (marked °) each degree is divided into 60 minutes (marked ') and each minute into 60 seconds (marked "); thus if the circle be large or small, the number of divisions is always the same, a degree...
Page 143 - ... for the least quantity of saliva which may be taken up by the brush has the effect of clouding and altogether spoiling the wash of colour on the paper. In place of this uncleanly method, the artist should have a piece of blotting-paper at his side — the more absorbent the better.
Page 43 - ... 3rd. If the ends of a cylinder be not at right angles to its axis, it is called an OBLIQUE CYLINDER. 4th. If a cylinder be cut by any plane parallel to its axis, the section will be a parallelogram, as EFG H} fig. 1. 5th. If a cylinder be cut by any plane at right angles to its axis, the section will be a circle. 6th. If a cylinder be cut by any plane not at right angles to its axis, passing through its opposite sides, as at K. L or M. JV, fig.