aE ees 
i ¥ ad ww 
38 R. HOSKING. 
the times of flow were recorded. The pressures: were 
reduced to equivalent pressures at 50°C. Knibbs has shown, 
that. the reduction formula, for experiments carried out at 
a certain temperature, may be expressed in the form 
Oi cfT= pW T okt (2) 
where C = 7, (1 + 1 R/L) - ae Pe 6 2), 
7gR 
oud c= V4 4318) (4) 
BiniTRge Ah tate) anita 
Hquation (2) is that of a straight line such that if1/T be 
taken as abscissz, and corresponding values of phT as 
ordinates, the line passing through the points so determined 
will intersect the axis of ordinates at a distance C from 
the origin, and make with the axis of abscisse an angle 
whose tangentise. Whenc has been obtained m is deduced 
by means of equation 4. 
Equation (3) may be written in the form 
CzgR* 
8V L 
The left hand side of the equation will have different 
values for different capillaries in the glischrometer. 
= me ( k 1 ns) 
Calling the left side K we have 
K=>%, + 24, R/L or-K' = y, + URE eee (5) 
where l = n ». 
This is the equation of a straight line such that if values. 
of R/L be taken as abscisse, and corresponding values of 
K as ordinates, the line passing through such points will’ 
intersect the axis of ordinates at a distance 7, from the 
origin, and make an angle with the axis of abscisse whose 
tangent is b. From value of b obtained in this way, 7 is: 
at once deduced. 
