and
are now known with that degree of precision, for there are four constant factors entering into all of the results in [Table X] and introducing uncertainties as follows: The coefficient of viscosity
which appears in the ³⁄₂ power introduces into
and
a maximum possible uncertainty of less than 0.1 per cent, say 0.07 per cent. The cross-hair distance which is uniformly duplicatable to one part in two thousand appears in the ³⁄₂ power and introduces an uncertainty of no more than 0.07 per cent. All the other factors, such as the volts and the distance between the condenser plates, introduce errors which are negligible in comparison. The uncertainty in