BRITAIN’S TEMPLE OF ACCURACY

Northern Advocate, 30 July 1938, Page 2 (Supplement)

BRITAIN’S TEMPLE OF ACCURACY

BRITAIN’S TEMPLE of accuracy, as the National Physical Laboratory at Teddington has been called, lived up to its reputation last year by improving precision instruments tp a degree of correctness hitherto unknown. In the Annual Report of the Laboratory for the year 1937. it is stated that a new type of clock has been devised and constructed by the electricity department which is of such remarkable accuracy that its error is only a small fraction of a second a year. This clock is nevertheless robust Another investigation earned out by this department was into the risk of explosion in the operating theatres of hospitals due to the accidental formation of‘electric sparks. It was found that it may be possible by the movement of blankets, etc., to produce sparks capable of igniting anaesthetic vapour.? The physics department has also made further advances in accuracy in the Measurements of Temperatures from about red-heat to 2000 degrees Fahrenheit. Only a few years ago such temperatures could not be determined

with a greater accuracy than 10 degrees and three years ago an accuracy of one-fifth of a degree was possible. More recent advances in instruments and technique now enable an accuracy of one-twentieth of a degree to be attained. A campaign for the reduction of noise has been carried out by the Laboratory for some years. Motor horns have been studied for the Ministry of Transport and some 200 listeners have assisted by recording their impressions of various types of horns to enable the Laboratory to determine which types combine the maximum tvarning with the minimum of assault on the nerves. It was found that horns which exceeded a loudness of about 100 phons (the phon is a unit of loudness) at 20ft. distance in the open in general cause annoyance and a recommendation has been made that the noise of motor horns should not exceed 100 phons at this distance. Work has also been carried out on the transmission of sound through walls and floors and it has been found that conduction of sound along water pipes can be eliminated by inserting a length of rubber tubing in the pipeline.