PASSAGE OF AIR THROUGH PIPES AND APERTURES. 105 



0*98 of aa inch diameter^ and terminated at one end by 

 a piece of wider tube, three inches long and two and a 

 half inches in diameter — 





Cubic inches of air per second, reduced to square inch | 



Length of tube of 

 0'9S inch diameter. 



of aperture of 



narrow tube. 



Air entering by the short length 



Air entering by the narrow 





of wide tube. 



tube. 



40 inches. 



642-7 





20 „ 



666-7 





10 „ 



714-2 





4 >, 



759'4 



728 



2 55 



787-7 



723*3 



I J) 



806-5 



730'4 



i „ 



810-9 



646-5 



i „ 



803-7 



578 flapping sound. 



a 



749*5 flapping sound. 



546 



s 55 



685-5 



547*5 



1 



666-6 



541-4 



In an experiment in which a flange with a hole of 

 one and a quarter inch diameter in its centre was placed 

 on the wide end, the quantity of air entering by the nar- 

 row tube reduced to the length of three-sixteenths of an 

 inch was increased from 546 to 600. 



The next experiments were made with a tube, 0-92 of an 

 inch outside and 0*8 inside diameter, successively reduced 

 in length. The inner sharp edge was removed at one end, 

 and the outer edge at the other end of the tube. It will 

 be seen that the greatest quantity of air flowed when it 

 entered at the end from which the inner edge had been 

 removed. 



Length of tube of 

 0'8 inch diameter. 



Cubic inches per second, per square inch of aperture. I 



Air entering the -^nd from 



which the inner sharp edge 



was removed. 



Air entering the end from 



which the outer sharp edge 



was removed. 



44 inches. 



24 » 



12 „ 



4 » 

 2 . ,, 



1 „ 



i. 



2 >j 



513-5 

 564 

 589-6 

 660 



685-2 

 726-3 

 699-6 



594-8 



473-2 



538 



573-4 



637-4 



668 



663-2 



594 

 526 



SER. III. VOL. I. 



