between the VISCOSn'Y OP LIQUIDS AND THEIR CHEMICAL NATURE. 449 
widely from the values afforded by Poiseuille and Sprung’s observations than they 
do from those of Slotte. The introduction of the Couette-Finkener correction 
reduces Traube’s coefficients at the higher temperatures by about 1 per cent. On 
comparing these corrected values, which vary irregularly with the temperature, with 
our own, they are found to be uniformly greater to the extent of from I'o to 4'2 per 
cent. These differences cannot be attributed to friction outside the tube ; the effect 
of this would diminish the values by about 0'8 per cent. 
The following table, showing the viscosity of water in dynes at every 5° between 0° 
and 100°, is based upon the observations of Poiseuille, Sprung, Slotte, and ourselves. 
The values due to Poiseuille are those calculated by Oscar Meyer, with the 
exception of that at 0°, which has been obtained by graphical extrapolation. 
Sprung’s values are those given in his paper, with the substitution of the Couette- 
Finkener correction for that of Hagenbach ; Slotte’s numbers have been corrected in 
like manner, and the values for every 5° obtained graphically. The values given by 
ourselves have been obtained in the same way. 
Table showing the Viscosity of Water in Dynes per scpiare centim. between 
0° and 100°. 
Temperature. 
Poiseuille. 
Sprung. 
Slotte. 
Tuokpe and Rouger. 
O 
0 
•01776* 
•01778 
•01808 
•01778t 
5 
•01515 
•01-510 
•01524 
•0150951 
10 
■01,309 
■01301 
•01314 
•013025 
15 
•01146 
•01135 
•01144 
•011335 
20 
•01008 
•01003 
•01008 
•010015 
25 
•00897 
•00896 
•00896 
•00891 
30 
•00803 
•00802 
•00803 
•007975 
35 
•00721 
■00723 
•00724 
■00720 
40 
•00653 
•00657 
•00657 
•006535 
45 
•00595 
•00602 
•00602 
•00597 
50 
•00553 
•00553 
•005475 
55 
■00510 
•00.5055 
60 
•00472 
•00468 
65 
■00438 
•004355 
. 70 
•00408 
•00406 
75 
•00382 
•003795 
80 
•00358 
•00356 
85 
•00337 
•00335 
90 
•00318 
•003155 
95 
•00301 
•002985 
100 
•00285 
•00283 
* The observation at 0°'6 was used in extrapolating this value. Poiseuille gives in addition a result 
at O^'S, but as it is cousiderably greater than it ought to be, having regard to the curve di’awn through 
the other observations, it has been neglected. 
t These values are taken from the curve connecting the special series of observations made on water 
between the temperatures of 0° and 8'’. 
MDCCCXCIV.—A. 3 M 
