INDUSTRIALAND ENGINEERING CHEMISTRY 1401 silicone decreased greatly during the first 24 hours of exposure, and thereafter there was little change. With tellurium the great viscosity change generally occurred between 72 and 168 hours of exposure. However, variable results were obtained with tellurium under an atmosphere of nitrogen. In some experiments the equilibrium viscosity was obtained after 24 hours.
ACKNOWLEDGMENTThe authors would like to express their appreciation to C. E. Cox for many of the viscometric determinations and to D. C. Smith for his cooperation in making the essential spectroscopic analyses discussed here.
LITERATURE CITED(1) Assoc, of Official Agr. Chemists, Official and Tentative Methods of Analysis, 5th ed., p. 174 (1940).