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the Laboratory. In 1901, from funds furnished by the generosity of Sir 

 Andrew Noble, equipment was provided for work on the fundamental high 

 temperature scale, which has since been continuously in progress. The 

 earlier work consisted in a comparison of platinum thermometers and 

 thermo-junctions with the gas thermometer, up to the highest tem- 

 perature which could then conveniently be measured with these instruments. 

 The account of this work published in 1903 was followed in 1904 by 

 a description of a new type of electric furnace, with a re-determination 

 of the melting-point of platinum. The subsequent investigations have 

 been directed mainly to the finding of some satisfactory refractory material 

 for the construction of gas thermometer bulbs for use at very high tempera- 

 tures. Other types of electric furnace have been devised in the course of the 

 work, and various difficulties have been encountered. lonization phenomena 

 in furnaces have been studied. 



Research on electrical units and standards dates from the time of the 

 foundation of the Laboratory. Dr. Glazebrook continued to serve as Secretary 

 to the Electrical Standards Committee of the British Association, and 

 continuity with the previous researches carried out by him for that Committee 

 was thus maintained. The course of the investigations at Teddington has 

 been marked by a series of papers on mercury standards of resistance, the 

 ampere balance, the normal Weston cadmium cell, the silver voltameter, 

 methods of high precision for the comparison of resistances, the variation of 

 manganin resistances with humidity, and a variety of other researches on 

 standard resistances, and standard cells. An ampere balance was constructed 

 in 1906-7, and a standard Lorenz apparatus for the determination of the 

 ohm in absolute measure, the gift of the Drapers 1 Company, has recently 

 been completed. An extensive research on the measurement of capacity 

 and inductance, including the construction of standards of inductance of 

 high accuracy, has been conducted. 



The Photometry Division has devoted continuous attention to the establish- 

 ment of satisfactory methods and standards for the measurement of the 

 illumination given by different sources of light. 



The investigations carried out in the Metrology Division have been 

 directed mainly to the construction and maintenance of standards of length, 

 and to the devising of suitable methods of length measurements of all kinds, 

 including measurements of screws and of tapes and wires for surveying 

 purposes. Many researches have been undertaken for the Engineering 

 Standards Committee a fully representative body working under the 

 auspices of the engineering profession and the Government for the purpose 

 of defining and providing practical and interchangeable standards in con- 

 struction. 



The research work in the Engineering Department has, for the most part, 

 been carried on with the continuous assistance and advice of the Institution of 



