VOL. 3, NO. 5
"'n
THE PECTICSUBSTANCES
513
Bogue "Colloidal Behavior," Vol. 2, p. 618.
" Loeb, "Proteins and the Theory of Colloidal Behavior," McGraw-Hill Book Co.,
1922.
I. Am. Chem. Soc., 46, 145 (1924). Biochem. J., 17, 510 (1923). Ibid., 19,257 (1925). " Science, 55, 1 (1922). P' W. H. Dore, Ind. Eng. Chenz.. 16, 1042 (1924). ?W.P. Wilson, Ibid, 17, 1065 (1925). 94 U. S. D. A,, Dept. Bulletin, No. 1323, Mar. 9, 1925. In
Microscopic Fossils to Aid Oil Seekers. A new scientific body composed of American geologists interested in the microscopic study of fossils has been formed, following the national meeting of the American Association of Petroleum Geologists a t Dallas, Texas. The society is composed of micropaleontologists throughout the country and is an organization of specialists within the larger petroleum body. Numbered among the pioneers in the movement to organize tliie society are several widely known paleontologists who for years have been devoting their time to research work in the field of microscopic investigations of fossils. During recent years it has been learned that one of the most authentic ways t o solve the riddle of the past is t o study the relics of the ancient world by examining the minute particles under the microscope. This instrument, long valuable t o the student of pathology and bacteriology, is rapidly becoming one of the most valuable assets in the hands of the student of prehistoric life.-Science Service Government Perfects System to Make Unbreakable Glaze. Housewives and incidentally the whole ceramic industry need no longer suffer meat losses in temper and in money from the cracking of the glaze on kitchen pots and pans. Experts of the U. S. Bureau of Standards have developed a system of measuriw the rate of expansion of the glaze used on pottery and enameled ware that will help manufacturers in making a product, the surface of which will not crack. All glazed ware consists of a body of clay or metal covered with a thin glassy layer having a composition quite different from that of the base. These two different materials expand a t different rates when heated. Thus there is considerable strain when the glazed ohject contracts on cooling down from its firing in the furnace. The strains suffered by this brittle glaze, only one two-hundredth of an inch thick, during t h e annealing process, reduce its resistance t o the many stresses it must endure in the course of a mare or less hazardous existence in the kitchen sink and on the dining-room table. Manufacturers, keenly alive to the vital bearing of these facL? on the development of their industry, have contributed generously t o scientific research on this problem in university laboratories, hitherto without avail. In a long series of experiments, in which the exact conditions of manufacture were reproduced, C. G. Peters and G. E. Merritt of the interferometric section of the Bureau of Standards have perfected a system for measuring the rate of contraction and expansian of the different glazes in commercial use. By applying this general method t o their individual problems, manufacturersof every variety of glazed ware, from bric-a-brac ~. to bathtubs, w i be ~ able t o ascertain their errors. They can then t&n out products the surfaces of which do not "craze" either in the making or subsequently, with consequent saving to hoth producer and consumer.-Science Service
