the Value of the Pitot Constant. 355 



possible as a result that the static pressure was not eliminated 

 from the recorded pitot pressures owing to a curvature in 

 the equipressure surfaces across the pipe. The pitot in the 

 recent work was placed as in fig. 2 A, 8 inches down a 



Fijj. 2 B. 



fir 



IaT 



Fijr 2 A. 



To Pressure. 



pipe AB. The pipe, which was 2 inches in diameter and 18 

 inches long was fitted with 12 side tubes £ 1? t 2 , &c, and was 

 screwed to a funnel at its lower end, the joint being made 

 as smooth as possible on the inside. The static pressure 

 slope down the pipe could thus be obtained by connecting a 

 gauge to any two of the side tubes, the rest being kep< 

 closed. It was found that at the highest mean velocities 

 used, this slope was only uniform down the pipe when a 

 piece of wire gauze was introduced across the section of the 

 pipe at its base. For work at low velocities the gauze was not 

 necessary. 



The pitot P could be set at any position along a diameter 



