caption: The image shows a black and white drawing of a brick wall with a diagram of a tree in the middle of it. The text at the top and bottom of the image reads "Plate IV, Plate 6, Plate 8, Plate 9, Plate 10, Plate 11, Plate 12, Plate 13, Plate 14, Plate 15, Plate 16, Plate 17, Plate 18, Plate 19, Plate 20, Plate 21, Plate 22, Plate 23, Plate 24, Plate 25, Plate 26, Plate 27, Plate 28".