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A notable addition to the " engineering " standards is a 7-ton stack of deadweights that enables calibrated lever systems in force measurement to be dispensed with. The machine is used almost exclusively for standardizing the portable " loadometers " used by transport licensing authorities to control vehicle loading. The machine gives greater accuracy than is possible with lever systems. New equipment for testing speedometers is also being put into commission. Equipment.—Standardized equipment commissioned during the year includes an a.c. potentiometer standardized by N.P.L., tungsten-filament lamps with radiant energy calibrations from the U.S. Bureau of Standards, thermometers re-calibrated in the range ol~loo°c.0 l ~100°c. by N.S.L. in Sydney, precious metals for international temperature scale definition, and a Secondary Frequency Standard (Marconi Type T.M.E. 1). Equipment about to be put into use includes a universal dynamometer voltmeter standardized by the N.P.L., and a 0-4 in. slip gauge comparator. PUBLICATIONS The following reports have been compiled during the year (these are additional to test reports and certificates) : No. 8/7/89 Operating Manual for Signal Frequency lonosonde. 8/7/90 Some Methods of Casting Tin Base Alloys. 8/7/91 Visit to the Radioactivity Centre N.I.T. during 1948. 8/7/92 Effects of Earthquakes on Dams. 8/7/93 Building and Ground Vibrator. 8/7/94 Geiger-Muller Counter Development. 8/7/95 Resistance Thermometer Units for Maraetai Dam. 8/7/96 Some Notes on Tool Design. 8/7/97 M.E. 7 Microwave Meteorological Radar Manual. 8/7/100 Comparative Ultra-violet Radiation Measurements at Lincoln and Lower Hutt. 8/7/101 Magnetic Separator. 8/7/102 Triaxial Testing of Soils and Rocks. 8/7/103 Transmission of Light Through Fog. 8/7/104 The Secondary Spectrum for Some Pairs of Chance Glasses. 8/7/105 A Short Stimulus Shock Therapy Machine. 8/7/106 Valve Tester—revised manual. 8/7/107 The Behaviour of Special Miniature Unsaturated Cadmium Cells. 8/7/108 The Technique of Wire Mounting Plated Quartz Crystals in Evacuated Holders. 8/7/109 A Smoke Density Recorder. The following publications by the staff have appeared this year:— Physical Review, Vol. 76, 1, Ist July, 1949: "Variation of Meson Intensity with Height." P. H. Barker. N.Z. Journal of Science and Technology, Section B, Vol. 30, 3, November, 1948: " The Measurement of Sola plus Sky Ultra-violet Radiation," and " Estimations of Hourly Values of Solar Ultra-violet Radiation in New Zealand." E. R. Cooper.

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