A.S.T.M. standards on insulating materials

The “Standards on Electrical Insulating Materials” recently published by the American Society for Testing Materials presents under a single cover A.S.T.M. standards that are in widespread use for testing and evaluating electrical insulating materials. The 1935 edition, 311 pages, gives 25 standardized methods of test and 10 specifications. The method of testing shellac has not been published heretofore. During 1935, revisions were made in a number of the test methods including those covering the following: varnishes, solid filling and treating compounds, molding powders, sheet and plate materials, laminated tubes and round rods, natural mica, and flexible varnished tubing.