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137. Reducing box for length
152. Mitre for field moulded bricks . 153–155. Method of obtaining camber slip
156. Camber arch
ditto, moulded 158, 159. Camber on circle
160. Curving bricks for same.
163. ditto, filled in with bird's-mouth key 164, 165. Modified Gothic
166. Elliptical or three-centred arch
ditto, string method
Mould for same.
Method for curving label bricks
Template for oriel. 1876. Base of pilaster.
PAGE 45 45 46 47 48 48 50 51 51 51 52 51 51 56 56 57 58 60 60 61 62 62 63 63 64 65 66 66 66 67 68 -68 69 69 70 71 70 71 72 73 73 74 75 77 78
188. Plan of pilaster . 189–192. Plans of pilasters 193, 194. Elevation and plan of moulded head of pilaster
195. Setting out dentils
196. ditto, breaking round pilasters . 197, 198. Boxes for cutting 9" moulded reveals 199–203. Architraves
204. Part elevation of panel 205–207. Moulds for cutting same
208. Moulded pediment 209, 210. Projecting keys.
211. Model showing cubic measurement
212. Plan of brick building 213–215. Diagrams, 1897 Examination 216-219. ditto, 1898 Examination . 220, 221. ditto, 1899 Examination. 222, 223. ditto, 1900 Examination.
79 79, 80
80 82 82 83 84 85 86 86 87 107 111 129 130 131 132
THROUGHOUT this work the terms “plan,” "elevation,” and "section" will be constantly used, and for the benefit of those who do not understand these terms, the following definitions are intended :
Plan. -A plan is a drawing representing any object as it would appear when looking down upon it. Thus; in drawing the plan of an 18" wall, not including the footings, draw the outside facelines and the joints as Fig. 2.
Elevation.—An elevation is the view of any object when looking directly at it. It may be vertical, or at any inclination to the horizontal plane. Elevations are known as front, back, and side; hence, again illustrating by means of the 18" wall, the front and back elevations would be shown as in Fig. 3.
Section.—A section is the view of an object representing it as it would appear when cut horizontally or vertically by a plane parallel or at any angle to the face or end. For instance, a vertical section, AB, through Fig. 3 would appear as Fig. 4.
It is understood by all those to whom this work will be of interest that a perfect knowledge of the scale rule and its uses is essential. To many this appears to be a simple matter, to others
a problem of some difficulty; and to the latter a few words of explanation, it is hoped, will enable them to master it.
Measurements. A single accent (denotes feet, a double accent (") inches, and (9) degrees.
The Reason for the Scale Rule.--An architectural drawing is the means by which the architect arranges with his client, and makes clear to the builder or craftsman the style of building or structure to be erected, and the sizes, shape, etc., of its different parts. It is evident that this drawing, or picture of the future building, does not represent its actual size, but is what is termed drawn to scale, that is, every part of the whole is brought down proportionately so many times less than the actual or full size. Thus, if a drawing be to a scale of one-eighth of an inch to a foot, every foot would be represented by }"; so that a wall 96' long would actually measure 96 eighths, or 12", on the drawing; and an opening in the wall 8' wide would appear as 8 eighths, or 1" wide.
How to read the Scale Rule.—When dealing with any particular scale, the student must remember that for the time being, and as far as he is concerned, the scale foot is actually a foot. Thus, taking a scale of 2" to a foot, he must dismiss from his mind the fact that it is 2" he is dealing with, and must treat it exactly as he would a standard foot. And, as the last-named is divided into inches, half-inches, etc., so will the scale foot be divided.
Taking off from and laying down to Scale.-In taking off any measurement from a drawing, the scale rule should be applied direct to the drawing itself. Many students make it a practice to take the measurement with the dividers, and then apply it to the scale, probably increasing the chances of error and risking damage to both the drawing and the scale rule.
For the same reason, in laying down a drawing to scale, the dividers should not be used.
When dealing with fractions of inches, it is advisable, for the sake of accuracy, to double the dimensions and halve the scale, until the fractions become whole inches. For instance, 21" on the 2" scale become 41" on the 1" scale, and 9" on the ?" scale.
How to construct a Scale.--It sometimes happens that a scale is needed that cannot be found upon an ordinary scale rule; it then becomes necessary to construct one. In doing this it must be borne in mind that the full size, or standard uneasurement, is a foot, and that the desired scale will be a proportion of this foot. Thus, if a scale of one-seventh full size be required, the full size,
or a line 1' in length, should first be laid down and equally divided into seven parts. Each part will then represent a scale foot, and in the same way in which the standard foot is divided
into twelve parts, or inches, so one of the scale feet will have to be treated.
There are several ways of accurately dividing short lines such as these scale feet; but the following method will be found quick and easy :-Let AB, Fig. 1, be the line to be divided into twelve parts, or inches. Upon B erect an indefi
nite perpendicular, BC; lay the scale B
rule with twelve equal divisions, say quarter or half-inches, with the first division on A, and rotate till the twelfth division cuts BC; mark off the divisions, and drop perpendiculars from these on to AB. The latter will then be found to be divided into twelve equal parts, or inches.
BRICKWORK MEASUREMENTS. The average length of a brick is 87", but with the addition of either a cross joint or a wall joint, it is reckoned as 9".
The width is 41", and for the same reason as given above, it is considered to be 44".
The average thickness is 23", and four courses with the bed joints will measure 11}", 12", or 12?", etc., according to the thickness of the joints. The usual practice is to build the work four courses to a foot.
A wall 1} bricks thick is usually called a 14" wall; 2} bricks thick, a 23" wall, whereas walls 2 bricks and 3 bricks thick are known as 18" and 27" walls respectively.
Course.—A course is the name given to one row of bricks in any thickness of wall, between two bed joints, as CD, Fig. 3.