In this part of the Ching’s book, he talks about the accessories of a foundation. He begins with stone, its qualities and types. According to ching, stone must have specific strength, hardness, durability, appearance, density and texture. The 3 main types of stone are Igneous Rock (Crystallization of molten magma), Sedimentary Rock (Removal of remains by glacial action), Metamorphic rock (changes in texture by heat and pressure). Some other types of stone are Rubble stone, which are the most rough, broken pieces. Crushed stone are the aggregate in concrete. Dimension stone are the uniformly shaped squares used for flooring and panels. And flagstone which are slabs used for flooring and vertical surfaces. Earlier in chapter 12 he defines bricks as Face (good for color and design) and Common or Building bricks (no treatment of color or texture). Their types vary from greater variation sizes and color range, to moderate, and narrow (FBX, FBS, FBA). Ching also warns us on page 6 chapter 12 that Efflorescence (exposed white powder of concrete from salts) can be treated with moisture absorption. Then, he labels with illustrations all types of blocks and their functions toward building a foundation. Furthermore in chapter 12, he introduces wood as natural, strong, lightweight, and friendly to use as a foundation or a design structure. The 2 major classes or wood are hard (from cherry or maple trees) or soft (from pine or spruce). Along with categorizing wood, he mentions that tree growth depicts strength and joints for enclosure. With his illustrations, he made clear that the grain direction depicts the use of wood as a structural material in the parallel direction to handle tension and compression well. However, tension that is perpendicular to the grain causes split! In addition, keep in mind that radial shrinkage can happen twice as much as tangential shrinkage. To protect your wood from fungi or bacteria (not 100%) dry its moisture to increase strength and stability. Moreover, on page 8, steel in described by Ching as high in strength, low-cost material, which must be coated with fire resistant materials, then he provides illustrations to the different shapes of steel. Finally, he provides the formula to make concrete (Cement+Water+Aggregate). Cement is a fine powder of burning a mix of limestone and clay. The water must be free of all organic materials. And aggregates must make up 60 to 80% of the concrete. The ratio of water to cement should be 0.45-0.60. Because concrete is not great in tension, it’s usually supported by reinforced steel. And now I summarized Ching’s part of his book about Masonry and materials in volumes.