﻿372 



M 



essrs. 



J. S. T. Roberts and E. Meigh on the 



while the flames from holes in very thin plates combine great 

 sensitiveness to sonorous vibrations of high pitch with con- 

 siderable immunity from the influence of disturbances of 

 other kinds. 



Table II. 







Flaring 

 Press, in 



Maximum 







Diam. of tube 



Length 



Sensitive- 

 ness Press. 



Degree 

 of 



Pressure at 

 which Sensi- 



m mm. 



(cm.) 



cm. of 



(cm. of 



Sensitiveness. 



tiveness 







water. 



water). 





disappears. 





6-25 



620 









0-7233 



36 

 2-4 

 1-4 



34-0 

 32-0 

 20-0 











6-9 



27-0 









0-9811 



4-6 



20-0 











2-5 



120 











9-75 



21-0 











555 



16-0 



16 



Minute. 



16 



1-183 



3-2 



9-0 







I 





1-6 



70 : 



7 



Minute. 



7 





0-9 



4-0 











1 5-85 



66 



6-5 



Slight. 



5-5 



1-666 



3-55 



5 



4-95 



y< 



4-90 



■ 2-8 



50 



4-95 



;J 



4-80 





1-6 



3-6 



3-6 



» 



3-6 





5-1 



2-2 



2-0 



Slight. 



2-0 



2-381 



: 3-92 



20 



20 



Moderate. 



20 





: 2-23 



1-4 



1-4 





1-4 





1-33 



10 











Thick 



; plate 







1 



1-054 



i 0-629 



9-4 



9-0 



Considerable 



8-7 





Thick 



i plate 









1-140 



: 0-313 



10-4 



10-0 



Considerable 



9-4 



In Table I. it will be noticed that the flaring-pressures for 

 the first five orifices are not greatly different, but that there 

 is a drop in the flaring-pressure when the diameter becomes 

 greater than, say, 1*2 mm. This would seem to indicate 

 that over a certain range of diameters of orifice the flaring 

 depends simply on what might be called the linear velocity 

 of flow at the orifice. With a view to testing this point we 



