Canon Moseley on the steady Flow of a Liquid. 359 



Table VII. 



\^ = 2-7664(e 2,25R -2-25R-l) 



T>1 " i 



J'Qi 













Qi- 



x*. 





No. 



h. 



I. 



R. 



(e 2-25R_ 2 . 25R _ 1) 



By experi- 



By 















ment. 



theory. 



150. 



•475 



100 



•0685 



•0125 



•0112727 



•18636 ! Cast iron, new. 



160. 



•805 



100 



•0940 



•0241 



•0313832 



•18671 j Cast iron, new. 



111. 



•670 



100 



•01795 



•00082 



0002558 



•40947 



Cast iron with deposit. 



123. 



1-61 



100 



•03975 



•00416 



•0033627 



•31928 



Cast iron with deposit. 



11s. 



1-441 



100 



0182 



•00085 



•0006268 



•25521 



No. Ill, cleaned. 



130. 



•737 



100 



•04005 



•0042 



•0031305 



•23433 



No. 123, cleaned, [men. 



83. 15-605 



100 



0413 



•0045 



•0209066 



•176526 



Iron covered with bitu- 



94. 12-156 



100 



•098 



•0251 



•18143946 



•13254 



Iron covered with bitu- 



57. 



2-80 



50 



•0205 



•001075 



•0017384 



•13178 



Lead. [men. 



59. 



7 61 



50 



•0205 



•001075 



•0030401 



•12423 



Lead. 



103 



0-156 



45 -02484 



•00151 



•00060699 



•077926 Glass. 



107. 



5 020 



45 J -02484 



•00151 



•00410166 



•10205 Glass. 



The steady flow of a liquid in an inclined pipe. 



In the experiments of M. Darcy on the flow of water through 

 circular pipes, the pipes were laid horizontally ; and the prece- 

 ding investigation refers only to such pipes. It may readily, 

 however, be adapted to the case of pipes upon a slope. If 1 re- 

 present the uniform inclination of such a pipe into the top of 

 which a liquid is poured so as to keep it full, and if / be the 

 length of the pipe, then the vertical height through which the 

 water has descended when it flows out of the pipe is represented 

 by I sin l, and the weight of the liquid which flows per unit of 

 time through a film whose radius is r is represented by 



■ 



Jo 



2ttw \ vrdr. Therefore the work U done by the 



weight 



of 



this volume of liquid in descending the pipe is represented by 

 the equation 



f 



U = 2irwl sin 1 \ vrdr. 



Substituting this value for U in equations (9) and (10) and pro- 

 ceeding as before, 





 .« 



1 + 



[©'->] 



(36) 



€ M- 



