Selected Bibliography Architectural Graphics | Page 202

BUILDING A DRAWING • To help us frame and compose a view as well as gauge the relative lengths and angles of lines, we can construct a viewfinder out of dark gray or black cardboard. • Another convenient sighting device is the shaft; of the pencil or pen with which we are drawing. • We hold the pen or penci l out at arm's length, in a plane parallel w our eyes and perpendicular to our line of ith sight. • To make alinear measurement, we can align the tip of the pen or pencil with one end of an observed line and use our thumb to mark the other end. Then we shift the pencil to another line and use the initial measurement to gauge the length of the second line. • To gauge the apparent slope of a line, we can alignone end of an inclined line w the shaft of thepen or pencil held ith vertically or horizontally. We gauge the angle between the two visually. Then we transfer this angular measurement to the drawing, using as guides the edges of the drawing surface that correspond to the vertical or horizont al reference line. • We can use the same reference lines to see which points in the image align vertically or horizontally with other points. Checking alignments in this way effectively controlsthe proportions and relations of both positive and negative shapes. 196 I ARCHlTECTURAL GRAPHICS