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Heat Pump.—A working model of a swimming-bath installation has been built and exhibited at Christchurch, Hamilton, and Auckland. An experimental unit is being installed at the laboratory for heating an office by circulating hot water in pipes under the floor. Applications of the heat pump to the dairy industry are being investigated in conjunction with the Dairy Research Institute. Strain-gauging of Engineering Structures.—Work is being carried out on the use of resistance strain-gauges for long-term investigations, and on their protection from moisture when used for such applications as measuring the strain in reinforcing-steel in a ferro-concrete building. Embedded Strain-gauges.—A prototype model has been completed and is undergoing stability tests. The design of the auxiliary electronic units has been completed and the first set is under construction. The design of a gauge assembly for quantity production is being examined. Vibratwns of Engineering Structures.—This work is concerned with the effects of earthquakes and other vibrations on structures. A general-purpose seismograph or vibration meter and a mechanical shaking-table for testing vibration-measuring equipment have been designed and are being built. A mechanical vibrator for investigating dynamic characteristics of soils and structures has been built, tested, and used successfully in the field by the Geological Survey. METALLURGY A wide range of queries and investigations has been handled, together with advice and practical assistance on heat treatment of metals and alloys, mechanical testing of metals, metallography, deposition of metals, radiological examinations, foundry practice, assessment of welds, investigation of service failures, hot and cold working of metals, and surface treatment of metals. A number of firms have been visited in connection with difficulties in the manufacture of castings, forgings, pressings, and structural members. Lead Reclamation.—The design, construction, and testing of an improved type of furnace for reclamation of lead from car batteries has been satisfactorily finalized. Moulding-sands.—Extensive tests on'the properties of local moulding-sands have been started. Green Island sand has been chosen for the initial examination, which will be conducted in accordance with standard foundry procedure. The reaction of the various molten alloys on this sand will also be studied. Ironsands. —Technical assistance and advice have been given to the State Iron and Steel Department in connection with the smelting trials at Onekaka in 1949. Some independent research has been carried out. DESIGN Fractionating Molecular Still.—An experimental model of a new type fractioning molecular still has been built, and tests are now being made of its fractionating power. Successful development of this type of still will allow molecular distillation to enter fields not now open to it, and should also increase the recovery of vitamin A from fish-liver oils from the present 70 per cent, to better, than 90 per cent.

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