Edinburgh Castle from West Princes Street Gardens, with the Ross Fountain

How to look at a Forrest

• Find the eye level first. In a close it is where the window sills stop tilting up and the lintels start tilting down.
• Follow one long edge of a tenement and count how many times the line breaks. That is the Prout inheritance.
• Squint until the hatching disappears. Count the values that remain; it is rarely more than four.
• Find the figures. Their heads sit on the eye level; their feet tell you how far down the close they stand.
• Look for the darkest passage (a pend, a doorway, the underside of a forestair) and notice what bright paper it touches.