312

FLUIDITY AND PLASTICITY

if.

TABLE VIII.—LAFAYETTE COLLEGE VISCOSITY RECOHD
Page I

Substance Pure Water Remarks Calibration

W. G. K.

Date

Observer

.0.46

Viscometer No. JL, Pycnometer No. 2

C'

Log C' = 8.37598-10 Log ~- =6.22122

~~~Q

Time

Manometer ,

upper read-

Temperature bath
Limb
Min-
Sec-
Time, seconds
ing, lower reading
Temperature
Sum difference =
Weight pyc.

utes
onds

ho

Start
Finish

20
L
5
7.0
307.0
259.46
259.46
21.2
287.58

28.12

231.34

20
R
5
8.2
308.2
259.48
259.48
21.1
287 . 60

28.12

231.36

P
hip
K
±hi PK±L
Po
Cip
C*2
P
t\ in cp
V
V
Remarks

0.9982
+ .44
-.79
-.35
230.99
1.76
229.23
1.0050
99.50

water mano-

-.44
-.79
-1.23
230.13
1.75
228.38
1.0052
99.48

meter

CALCULATION OF CONSTANTS
Let us use the above data for water at 20° to show the method
of calculation of constants, etc. We record the sum of the upper
and lower manometer readings merely as a check against error
in reading, since this sum should be constant. With our instru-
ment V = 4.0 ml, and I = 7.5 cm hence Cf = 0.02377. The
value of 231.34, corrected by Table II for K gives
200 cm at 21.2° = 0.69
30 cm at 21.2° = 0.10
1.34 cm at 21.2° = 0.00
Total correction = 0.79
pi = 231.34 - 0.79 = 230.55 cm