MR. J. E. H. GORDON ON MEASUREMENTS OF ELECTRICAL CONSTANTS. 437 
Among the uncorrected, values the extreme difference from the mean is + 2\5 per 
cent., which shows that though the correction is a rough one it gives numbers more 
nearly true than the uncorrected experiments. 
The melting point of the paraffin was G8° C. 
Bisulphide of carbon .—The liquid was contained in a glass trough. In this case cq 
was the reading when the empty trough was placed in a b; ci 2 the reading when it 
was full. The trough was 7 inches wide and 9 inches high: b is its internal 
thickness. 
We have from direct measurement 5=-637. The external thickness was '779. The 
thicknesses of the sides '076 and "066, respectively, and '7 79 — ('076 + '066)= ’637 ; 
showing that the inside and outside scales of the callipers agree very well. 
The experiments had to he made somewhat hastily owing to leakage of the 
bisulphide. 
6=-6 37 
cq 1*192 1*189 1T92 
cq 1-471 1-467 
cq 1-176 1-173 
Mean cq= 1*469 
Mean cq=lT84 
cq—cq "285 
K= 1*81. 
The following table gives a general summary of the results of the experiments, and 
compares the values of K obtained with those given by various former experimenters A— 
* Some of the numbers given in the third column are from ‘ Units and Physical Constants,’ by 
Professor Everett, p. 134 (Macmillan, 1879). Where no reference is given, the number is from a list 
sent to me by Professor Maxwell. 
