News | Published:

U.S. Bureau of Standards

    Naturevolume 134page188 (1934) | Download Citation

    Subjects

    Abstract

    THE annual report of the U.S. Bureau of Standards for the year ended June 30, 1933, is very satisfactory, notwithstanding the industrial depression. New determinations of the values of the electrical units have been made by absolute measurements. In the case of the ohm, the inaccuracy was only of the order of about one in a million. The Bureau has fixed the visibility factors for commercial types of electric lamps by means of coloured filters. These values have been adopted internationally. A piezo-electric standard has been constructed which maintains a wave frequency constant within one part in ten million for several hours without adjustment. The accuracy of the 5,000 kilocycle radio transmissions which are disseminated periodically has been increased to one in ten million.

    About this article

    Publication history

    Issue Date

    DOI

    https://doi.org/10.1038/134188a0

    Comments

    By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

    Newsletter Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing