ADDENDUM National Bureau of Standards Circular 572 Calibration of Line Standards of Length and Measuring JAN 22 1960 (Section 2, page 1) A redefinition of the value for the yard became effective July 1, 1959. The new definition of the yard is 1 yard = 0.914 4 meter exactly. From this definition it follows that 1 inch equals 25.4 millimeters. These same equivalents have become effective as of the same date in the national standards laboratories of Australia, Canada, New Zealand, South Africa, and the United Kingdom, thus bringing about international accord on this definition among the English-speaking nations of the world. In the United States, one exception has been provided at the request of the U. S. Coast and Geodetic Survey. LIBRARY UNIVERSITY OF CALIFORNIA Any data expressed in feet derived from and published as a result of geodetic surveys within the United States will continue to bear the following relationship as defined in 1893: The foot unit defined by this equation will be referred to as the U. S. Survey Foot and it will continue to be used, for the purpose given herein, until such a time as it becomes desirable and expedient to readjust the basic geodetic survey networks in the United States. UNITED STATES DEPARTMENT OF COMMERCE NATIONAL BUREAU OF STANDARDS Lewis V. Judson DEPARTMENT Calibration of Line Standards of Length and Measuring Tapes at the National Bureau of Standards AMERICA Sinclair Weeks, Secretary • A. V. Astin, Director National Bureau of Standards Circular 572 Issued June 4, 1956 Supersedes Circulars 328 and 332 For sale by the Superintendent of Documents, U. S. Government Printing Office, Washington 25, D. C. |