## Mechanical Drawing

How To Draw Animals Step By Step

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to m, and draw through this a line parallel to ab; measure also to n, and draw nn. From m measure on both sides the distance mo; also from n to n, n; these points are the centres of the circles shewn in the sketch, the method of putting in of which is still further elucidated by

Example 32. Let the line cd, fig. 32, correspond to mn in fig. 31, ab to nm, and fe to nn. From the point of intersection of these lines with cdy describe the circles as in the drawing. On each side of cg? draw the lines

m,m; and parallel to same lines, lines oo touching the circles. From fe, ab lay off to nn lines equal to m; and from m, to 88 equal to the distance of the line m from d; joints, and the points corresponding.

Example 33. To draw the basement arch below the principal entrance to a house as in fig. 35. Draw the line ab, and at right angles to it a line from c. Measure from c to a and b. From same point, with c/as radius,

ciescribe the semicircle ff From c measure to d, draw a line through this parallel to ab. Measure from d to e, e; join ae, be; put in the key-stone dg. Divide be into five equal parts, and from these points, parallel to ab, draw, lines through dg to the line ae. From s measure to t, and draw lines on each side the key-stone dg, parallel to its sides. From t measure to k. Divide kf into five equal parts. From i measure to h; from c, with ch, describe a dotted semicircle nhm, this will give the termination of the lines drawn from the points on be. Join these with lines to the points found in the part of the. circle kf.

Example 34. To describe the ornament (part of a verandah) in fig, 84. Let aft be the breadth; bisect it in c; draw cd at right angles to aft. Draw on the board lines corresponding to these; the line cd will be that on which the centres of the complete circles are found. From c measure to a and ft ; draw af be; the centres of the parts of circles within the complete ones will

Example 34. To describe the ornament (part of a verandah) in fig, 84. Let aft be the breadth; bisect it in c; draw cd at right angles to aft. Draw on the board lines corresponding to these; the line cd will be that on which the centres of the complete circles are found. From c measure to a and ft ; draw af be; the centres of the parts of circles within the complete ones will

to aft. With ac, from the point m, describe a circle gmL With gh, the diameter of the outer circle, lay off on cd from the point m to the points n and 0. Through these draw lines parallel to aft, as snt. From ra, with radius ac, describe a circle snt. Through the point where the two circles touch, draw a line vv parallel to aft, cutting af be. With radius ac, from r, t>, describe semicircles as in the sketch. The centres of the remaining circles will easily be found from the foregoing instructions.

Example 35. To draw the window in fig. 35. Bisect aft in c; draw cd; join gg and oo by dotted lines as in the copy. On the board draw lines corresponding to ab,cd. From c measure to a, ft, and put in the cill acft, as described in fig. 10. From c measure to h, e and n. From h measure to g, g, and |foom these point« draw lines parallel to cd; draw gm. From e with ef describe the semicircle ; and from n, with »o, ono. . Perpendicular to ono draw lines to p,p; with the radius of the circle ono measure top, p; from these points with same radius describe the quadrants o&, as. From.«

draw st parallel to aft. Finish the circles as in the copy. The method of putting in the part from g to v will be more fully described in

Example 36. Let m,p in fig. 36 represent similar points in fig. 35, so the inner circle, and st the horizontal line at termination of dripstone. From the point m draw am perpendicular to the line from m; at a (¿aw aft equal and perpendicular to am; from ft, be; from c, cd; and from d, de; all equal to am, and at right angles to one another. Join e to ts by a line parallel to pn. Let go be the distance of the circle gh from so; from p, with pg, describe a quadrant to h, making the point h distant from the line st equal to go. In like manner describe nr. From h and r draw lines

fig. 36.

hm, rx parallel to st From the points m, t, with radius greater than half the distance, describe arcs meeting in v; from v, with same radius, describe the arc mt; join xm.

Example 37. To draw the Elizabethan gable in fig. 37. Divide aft in the point c; draw cd. Corresponding to these draw lines on the board. From c measure to a, and put in the part below, as in the sketch. From c

measure to d, and draw fdf parallel to ab. From d measure to ee andff; from c measure to g, and from gy with gh, describe the quadrant hm. From m draw mi parallel to cd; from f, with radius /n, describe the arc meeting the line u Finish as in the part to the left of die sketch. * Example 38. To describe the flutes and fillets in fig. 38. Let ab be the diameter of column, bisect it in c; draw cd. Draw on the board lines corresponding to these, and from the point e, with cb, describe the semicircle adb, representing half of the column. Riaectthe quadrant ad in the point

e, and divide the arcs ae, ed by points h, m. Mark the position of these by radial lines from c, as in the copy. Divide the part ag into eight equal parts ; and with three of these as radius, from the points in the quadrant, as <7,/, &c., describe semicircles. Six parts will thus be given to each flute, and two to each fillet : and the column will have twenty-four flutes.

Example 39. To describe the flutes in a Doric column without the fillets, as in fig. 39. Proceed as in la3t example, by dividing the quadrant bee into

fig. 39.

six equal parts, as em, mn, giving to the entire column twenty-four flutes as before. Draw radial lines from b. Divide af into four equal parts, and lay one of these on ab produced to e; from b, with be, describe a semicircle as emn, cutting the radial lines. Bisect af in o, and with fo as radius, from the points where the dotted semicircle intersects the radial lines as centres, describe the arcs as in the copy. Another method is shewn in

Example 40, fig. 40. Describe a semicircle ade, and divide the quadrant bad into five equal parts, so as to give twenty flutes to the column. Produce ab to/; bisect ae in h, and from e lay off eh to m; join hm, and

fig. 40.

with distance he lay off on the radial line be to n. From b, with bn, describe the dotted semicircle no. The centres of the flutes are placed where the radial lines intersect this semicircle. From n, with nm, describe the curve mh, and draw the others in the same manner.

Example 41. To describe the flat flutes and fillets as in fig. 41. Describe the semicircle adc, and divide the quadrant bad into six equal parts ; di

vide ae into five equal parts. With two of these from the radial line, lay off on each side, as / h. With one part lay off from c to m, and from ft, with bm, describe a semicircle cda; complete the diagram as shewn. This will give the depth of the flutes, one; the width, four; and the width of fillets, one.

Example 42. To describe the cabled moulding in fig. 42. Divide the semicircle acdin the same proportion as in fig. 38, giving an equal number

as in that example. From ft, with be, describe the semicircle effi From the points where the radial lines intersect this, as centres, with radius ae, describe the curves as in the copy.

Example 43. To delineate the flutes in a pilaster, fig. 43. Let aft be the breadth; divide it into twenty-nine equal parts: each flute is three parts in breadth, and each fillet one. This gives to the pilaster seven flutes and

eight fillets. Draw ac, bd at right angles to aft; and parallel to these lines, from the first point next these, as at e; at the fifth of these points, as at /; the sixth, at g, draw lines. The first fillet is ac, the first flute ef; fg the second fillet, gh the second flute, and so on. The centres from which the termination to the flutes are described will be on the line ss, this being intersected by lines drawn parallel to a e, drawn through a point bisecting the fillet efigh, &c.

Example 44. To describe the curves in the twisted Doric column in fig. 44. Proceed as in

Example 45, fig. 45. Draw the centre-line aft, and the line of base cc, the width dd being that below astragal in capital; join dc, dc. With distance cc, lay off on aft from a to c, and draw through this point the line gh, parallel to cac. With half cc, as ac, lay off on aft to/ From/as centre, with fg as radius, describe the arc gc; with fh as radius, from the points c and h as centres, describe arcs cutting in m; from m as centre, with mh as radius, describe the arc he. Make en equal gh; with eg, or