8. W. Holman—Method for Calibrating Thermometers. 281 
assumed as zero, and call this B. Then A+u’+wu’+ ... + 
ures ere are thus n spaces of equal volume between A 
and B, and these correspond each to “th of the interval B—A. 
Hence the true reading (which, however, it is not necessary to 
compute numerically) at the point— 
A is A 
Atul A4— (BLA) 
siete eek 
B me 
And the error obtained by subtracting the true readings, as 
given in the right-hand column, from the corresponding actual 
readings, given in the left-hand column, at 
A is 0 
Afu — * Atw {A+— (B-A)} =u'—— (B-A) 
A+u’ tu” [74 wu! —4— (B-—A) 
B 5 0 
Tn selecting B it might have been assumed equal to A+w’, 
thus making n=1. is would somewhat simplify the calcula- 
tion, and would be of equal accuracy, but is objectionable from 
the fact that, in general, this volume would differ considerably 
rom the average volume obtained when m has a greater 
value (always an integer), and the resulting series of errors 
would assume larger numerical values. 
he errors or corrections are, for purposes of interpolation, 
most conveniently represented graphically by a smooth curve 
through points with abscissas proportional to the direct read- 
ings, 
A, A+u’, A+u’/+u”, ete., 
equal to zero, distributing the difference at that point pro- 
portionally to the scale readings, among the errors at the in- 
