APPENDIX D
The measurements of Poiseuille, being somewhat inaccessible
but of great practical as well as historical interest are given
in detail in the following tables. Comparative values of the
viscosity of water by various observers with all of the known
corrections made are given in Table II. Since specific viscosities
are often used, relative to water at different temperatures, we give
the viscosity for water for every degree from 0 to 100 in Table
III, and in Tables IV and V we give the fluidities of alcohol-water
solutions and sucrose-water solutions as possible calibration fluids
where water would be too fluid. For changing viscosities to
fluidities the table of reciprocals (Table VI) is very convenient.
To get the reciprocal of a number such as 1.007, the first part
of the table is not very convenient on account of the large
differences used in enterpolation. If however one uses instead
10 X 0.10070 in the latter part of the table, fifth column, p. 343,
the number 9.93 X10"1 is found as the reciprocal without enter-
polation. The part of the table from 10.0 to 15.0 may also be
used for this same purpose, in which case the reciprocal of 10.07
is found in the ninth column.
A table of four-place logarithms (Table VII) are included,
and are often sufficiently exact, since viscosities are generally not
more accurate than one part in 1,000.