516 



Mr. R. Hosking on the 



With Tube I. in the glischrometer, the formula gives con- 

 stant values up to a pressure o£ 35*4 cms. of mercury, when 

 the time of flow is about 22 seconds. It will be noticed that 

 at this point the kinetic energy correction is more than 

 60 per cent, of the viscosity, and the average velocity in the 

 tube is 400 cms. per sec. 



In the case of Tube II. the formula breaks down suddenly 

 at a pressure between 35' 7 cms. and 36*9 cms., the time of 

 flow being about 24 sees., and the correction at pressure 

 35*7 cms. more than 55 per cent, of the viscosity. The 

 velocity in this case is 370 cms. per sec. 



Eesults at 50° C. with Tube III. ir 



Glischrometer. 



Pressure 



Time of 



Second 



Yiscosity 

 (double 



readings) 

 rj X 10 5 . 



Yiscosity 



(*) 



Flow (T) 



Term 



(mean) 



(Approx.). 



(Approx.) 



X105. 



■n x 10 5 . 









f 552 "1 





7'3 cm. 



54-6 sec. 



156 



J55ll 

 1 550 ( 

 1549 J 



550-5 



11 „ 



41-6 „ 



205 



J 5531 

 1 561 J 



552-5 



15 „ 



33-9 „ 



252 



{ 552 \ 

 1551/ 



551-5 



20 „ 



26-5 „ 



323 



|554 1 

 \554J 



| 555 I 



554 











30 „ 



19-9 „ 



430 



i 558 y 

 | 556 | 

 \559J 

 [558] 



557* 



35 „ 



17-9 „ ' 



478 



\ 562 I 

 1 565) 



562* 











( 615^ 













607 1 













617 1 





40 „ 



17-0 „ 



500 



■ 



613}- 

 604 1 

 609 



612* 









leu; 





Mean -00552 



For Tube III. the figures are, pressure between 20'4 cms. 

 and 30*4 cms., time of flow less than 26 sees., second term 



