An amendment to Article 4, Section 2 was also presented, adding to the memhership of the Executive Committee the most recent past chairman of the Division. On motion these changes in the constitution were adopted, subject to ratification by the Council of the American Chemical Society. Chairman Segerhlom had previously appointed a nominating committee consisting of L. W. Mattern, Chairman, Hamson Hale, and M. V. McGill. This committee reported a t the final session and recommended the election of the following officers for the ensuing year:
Chairman, B. S. Hopkins, University of Illinois, Chicago, Illinois Vice-chairman, G. W. Sears, University of Nevada, Reno, Nevada Secretary, Ross A. Baker, Syracuse University, Syracuse, New York. Members of the Executive Committee: Wilhelm Segerhlom, Phillips Exeter Academy, Exeter, New Hampshire W. D. Engle, University of Colorado, Boulder, Colorado M.. V. McGill, Lorain H. S., Lorain, Ohio. Ballots were cast for these officersand they were duly declared elected. On motion the Division adjourned. B. S. HOPKWS,Secretary
Chromium on Printing Plates Saves Money for U. S. Mint. That a thin film of metallic chromium, electroplated upon a metal currency printing plate, would cause the plates to withstand the wearing action of the printing presses better than if the plates are made of the hardest steel, is the outcome of the tests of this process a t the U. S. Bureau of Engraving and Printing. Not only do the plates wear longer, but they cause the intricate detail of the bill designs to come more sharply into relief, thus affording further protection against counterfeiting. The method, worked out by chemists of the U. S. Bureau of Standards in collaboration with officials of the engraving bureau, deposits a film of metallic chromium thinner than an ordinary sheet of paper upon a finished steel or copper-nickel plate. After machining to sizes suitable for clamping on the presses, of which there are several hundred in daily service; .the plates are-placed in a special chromium plating bath. Under carefully controlled conditions the deposits an the plates have a beautiful silvery luster, the operation requiring in h e case of the nickel plates only thirty minutei,'and of steel twice as long. Harder than the hardest steel, the plates yield from 50,WO to 100,000 impressions of eight bills each, and in some cases considerably higher numbers. An additional advantage of the method has heen the discovery that after such a run the chromium film may he removed chemically and a new film put on, thus obviating the necessity of makmg a new plate. It is predicted that the method, already used to some extent on plates from which labels and similar commercial articlesare printed, will find a much wider usage in the "shells" or electrotyper's plates from which books and periodicals are producdL-
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