The Building Science Series disseminates technical information developed at the National Bureau of Standards on building materials, components, systems, and whole structures. The Series presents research results, test methods, and performance criteria related to the structural and environmental functions and the durability and safety characteristics of building elements and systems. These publications, similar in style and content to the NBS Building Materials and Structures Reports (1938-59), are directed toward the manufacturing, design, construction, and research segments of the building industry, standards organizations, and officials responsible for building codes. The material for this Series originates principally in the Building Research Division of the NBS Institute for Applied Technology. The publications are divided into three general groups: Building Systems and Processes: Health, Safety, and Comfort: and .Sturctures and Materials. Listed below are other publications in the category of-Structures and Materials • Interrelations Between Cement and Concrete Properties: Part 1, Materials and Techniques, Water Requirements and Trace Elements. (C13.29/2:2) 35 cents • Weather Resistance of Porcelain Enamels: Effect of Exposure Site and Other Variables After Seven Years. (C13. 29/2:4) 20 cents ' • Interrelations Between Cement and Concrete Properties: Part 2, Sulfate Expansion, Heat of Hydration, and Autoclave Expansion. (C13. 29/2:5) 35 cents • Some Properties of the Calcium Aluminoferrite Hydrates. (C13. 29/2:6) 20 Cents • Organic Coatings, Properties, Selection, and Use. (C13.