194 Master Minds of Modern Science 



Laboratory as accurate it must register any temperature 

 to within one-tenth part of a degree Fahrenheit. 



In yet another part of this building experiments are 

 conducted for the purpose of solving cold-storage prob- 

 lems. Here scientists are at work studying the heat- 

 insulating properties of different materials and investi- 

 gating methods of regulating the temperature, humidity, 

 ventilation, etc., of cold-storage plants. A member of the 

 staff recently travelled to Australia in order to investigate 

 the conditions affecting the transport of apples to this 

 country, and to advise on the provision of suitable instru- 

 ments for making the measurements of temperature 

 necessary to ensure that the fruit reaches this country in 

 perfect condition. 



At Teddington also is the British Radium Standard; 

 by this is measured the amount of radium contained in 

 any sample of radio-active ore submitted. Here also is 

 tested the protective value of materials used in X-ray 

 installations, and the Laboratory also examines the 

 X-ray equipment used in hospitals. 



It is no exaggeration to say that there is hardly a 

 single department of public life with which the National 

 Physical Laboratory is not concerned. Propeller designs, 

 the efficiency of gears and lubricating oils, steam-pipe 

 insulation, the strength of cylinders for compressed gas, 

 the heating of underground mains, wireless valves and 

 transformers, the manufacture of optical glass, the 

 analysis of tides, the velocity of projectiles, aeroplane 

 fabrics — the scientists of the Laboratory are interested in 

 them all, and in many more subjects of scientific inquiry 

 which we have not the space to mention here. 



But there is one more department which must be 

 mentioned. This is the High- volt age Laboratory, where 

 a million-volt electrical current can be produced at 

 will. 



It is an enormous hall, forty feet high, and at one end 



