﻿984 Dr. Thomas on Discharge of Air through Small 



seen from a consideration of fig. 7, in which the volumes of 

 air entrained per unit volume of air in the issuing jet are 

 plotted as ordinates against the pressures as abscissas, in the 

 case of orifices nos. 1-10. Carves 1 to 8 inclusive indicate 

 the normal behaviour of the jet as regards air-entrainment. 

 It is seen that a diminution in the size of the orifice is 

 accompanied in each of: these cases by a greater air-entrain- 

 ment per unit volume of air in the jet. This point is of 



5 10 15 20 



PRESSURE (CMS. OF WATER). 



importance in the design of gas-burners operating on the 

 Bunsen principle, as it is to be anticipated that a greater 

 degree of primary aeration of the issuing jet of gas can be 

 effected by diminishing the size of the ejector orifice, and 

 employing a multiple-orificed ejector in place of an ejector 

 provided with a single orifice of greater area. In the 

 practical application of this result, however, the several 



