Radiation emitted in Gaseous Explosions. 



67 



2. It will be convenient to describe here very briefly the 

 •experimental arrangements under which these films were 

 taken. The gaseous mixtures were exploded in a cylindrical 

 cast-iron vessel 30 cm. in diameter and 30 cm. in length 

 (shown in fig. 1). The pressures of the gaseous mixtures 



Fie. 1. 



Bo/ometer^ 



during explosion and subsequent cooling were measured by 

 means of a Hopkinson optical indicator which threw a spot 

 of light on to a revolving photographic film. The radiation 

 was measured by means of a platinum bolometer connected 

 with a reflecting galvanometer which also threw a spot of 

 light on to the same revolving film. The bolometer was 

 protected from the hot gaseous mixture by means of a plate 

 of fluorite as shown in fig. 1. The fluorite transmits almost 

 exactly 95 per cent, of radiation of the wave-length emitted 

 by an exploded coal-gas and air mixture. After making an 

 allowance of 5 per cent, for the absorption of the fluorite and 

 5 per cent, for reflexion from the blackened surface of the 

 bolometer, it is considered that the measurements from 

 the films give radiation values of a high degree of accuracy. 



F2 



