Figure 42 is a schematic line drawing of a ladder leaning against a perpendicular wall. It is a side view so only the thickness and height of the wall and only the side of the ladder are visible. A brick pattern is used to identify the wall. The rungs of the ladder are represented by 18 circles at regular intervals up the side of the ladder. The ground is represented by a straight horizontal line. The ground line, perpendicular wall and the ladder create a right-angled triangle configuration. The angle between the ground line and the ladder is identified as being 75 degrees.

 3.3 New materials