HE CONSTRUCTION of models and demon-(12) High explosive bombs. T s t r a t i o u apparatus develops both the academic 1 :;; $ $ O~~~~~~~$~~l e 03s, and mechanical skills of superior students in high-(15) Iodine plant.school chemistry. Such projects offer an e~cellent (16) Incendiary bombs. opportunity for students to plan and carry out their own (17) Liquid air plant. purposeful and self-directed activities. Moreover, (18) Liquid ammonia plant. Cf., ibid., 8, 2062 (1931). they tend to satisfy the urge to create and enable (I9) Liquidcarbon dioxide (20) Lime kiln.students to correlate the knowledge and s k i s acquired (21) ~~~~f~~~~~~ of steel,* in other subjects with their work in chemistry.(a) Bessemer process.The student should first select a chemical principle, (b) Open hearth process. process, or concept or an important application to (22) Manufacture Of acid.(a) Contact process. Cf., ibid., 8, 2239 (1931).modern life. A model or demonstration apparatus (6) Lead chamber process. Cf., ibid., 18, 47 (1941). should then be planned to illustrate or demonstrate (23) Manufacture of rayon. the principle or idea selected.' The student should (24) Molecular still. gather or collect as much of the material needed in (25) Nitric acid plant. the completion of the project as possible, men (26) Paper makingmachine (Fourdrinier). (27) Pasteurization plant. completed i t should be neat, attractive, and dynamicz (28) refine,,,. Carefully planned inspection trips to such museums (29) Refrigerating machine. as the New York or Chicago Museum of Science and (30) Respiratory calorimeter. Industry and the National Academy of Sciences, (31) (32) Solvay process." Washington, D. C., will serve to familiarize the students (33) Sewage disposal plant, Cf,, ibid., 17, 167 (1940), with examples of skilfully constructed and protected (34) Synthetic plant. scientific exhibits. Close-up pictures of chemical (35) Synthetic rubber plant. plants and laboratories and their surroundings are of (36) Typical oil field. tremendous value to students the con-(37) Unexploded bombs (model showing how to detect the presence of unexploded bombs). struction of models. (38) Water purification plant. Some examples of suitable models and types of (a) Aeration plant. demonstration apparatus which high-school chemistry (b) Chlorination plant.teachers may appropriately lead their students to (6) Filtration plant.* "discover" are given below. Many of these should (39) Water works plant.