VISCOSITY OF WATER BY THE EFFLUX METHOD. 137 
Viscosity of Distilled Water at O° C., computed from the efflux 
measurements of various investigators. 
Observer. Date. Expts. Tube. Temp. No: 
Poiseuille 1846 series glass 0°- 45° 001786 
Jacobson 1860 4 x 16°.7 1808 
s > 4 : 15-2 1800 
” ” 3 ” 11°3 1867 
% iy 2 Z 122 1770 
” » 3 brass 13°4 1755 
” 5 3 7 15-7 1809 
% s 1 ie 16-7 1806 
” ; 5 : 15-2 1786 
” i 4 ‘ 12°8 1778 
” ; 7 ; 16-5 1794 
Sg ” 5 ” 16°4 795 
Hagenbach 1860 4 Pa 17°4 1844 
Sprung 1876 21 eee Ty 1773 
Rosencranz 1877 2 a 42°55 1797 
Srottin 1879 2 14.9 —«:1798 
Slotte Oo ea 10° 1814 
Wagner 1883 4 . 15° 1797 
Reynolds 22 lead 5° — 12° 1834 
Konig O86... k glass 16°.8 1771 
Couette 1890 2 copper 16-4 1819 
3 ” 3 white metal 18-5 1817 
3 paraffin 12-6 1853 
23. The relative fluidities of distilled water at ordinary pressures 
: temperature 0° to 50° C.—Small errors in the dimensions of 
tubes prejudice but slightly the reduction of the relative fluidities, 
IMasmuch ag they affect only the correction for the fall of pressure 
at the entrance of the tube. That the dimensions given are, with 
the exception of Graham’s, sensibly correct, is evident from the 
that the absolute values of the viscosity derived from them 
se nearly identical, The results however do not exhibit as 
ms ect an agreement as one might perhaps have expected. The 
ue for 0° C. has been taken as 1000 instead of unity. 
