Among the present activities of this laboratory, some of which have been mentioned above, are: Preparation and revision of specifications, Study of miscellaneous analytical methods, Weather exposure tests, Accelerated tests intended to simulate weathering, Study of methods of measuring consistency of paste and liquid paints, Study of methods of measuring hardness of paint and varnish surfaces, Study of methods of determining hiding power of paint, Study of methods of measuring thickness of pain tand varnish films, Study of methods of preparing paint and varnish that can be separated from the underlying surface and determination of the strength, elongation, toughness, etc., of such films and change in such properties under varying conditions of aging, Study of the properties of both clear and pigmented nitrocellulose lacquers. Publications Official Bureau of Standards publications in this field include ten Technologic Papers, one Miscellaneous Publication, two Circulars of general information and twenty-seven Circulars giving Standard Specifications for a wide variety of paint and varnish materials. The Specification Circulars contain complete directions for sampling and testing. In addition to the official pi~blicationsa number of papers have been contributed to various journals. A list, of these publications will be furnished on application to the Bureau.
Diphtheria Deaths May Be Negligible by 1930. Preventive medicine has scared a real triumph over diphtheria. A survey of the mortality statistics of this once deadly disease reported t o the American Medical Association shows that in 191G14 only thirteen cities averaged death rates under 10 per 100,000; in 191&19 only eighteen cities could be so classed: hut in 1924 there were thirty-seven and in 1925 forty-nine with diphtheria death rates lower than had ever been known before 1910. There is little doubt, medical authorities say, that this amazing reduction can be attributed largely t o the increasing practice of immunizing school children with toxinantitoxin mixtures or with antitoxin, This opinion seems to be borne out not only by observation in single cities like New York where this method has been extensively used, but by the rapid decline in diphtheria mortality throughout the country. Antitoxin, as a curative agent, is due considerable credit but the fact that the death rate has dropped so decisively since the immunization measures have been applied indicates that it is the main factor. According t o editorial comment in the Journal of the American Medical Assodation, diphtheria may be an almost negligible factor in the mortality returns of 1930, if the improvement of the last three years continues.Science Service
