ELECTPJC DISCHARGES IX GASES AT LOW PRESSURES. 
417 
For 1800 volts the figures are approximately : 
Distance between electrodes 
in niillims. 
1 
2 
3 
5 
10 
Discharge pressures in niillims. 
of mercnry. 
•817 
•421 
•274 
.1(34 
•0892 
where the pressures are almost in the required ratio, being 9^2 : 4-8 : 3-0 : 1-9 : 1. 
For 500 volts tlie numbers are : 
Distance between electrodes 
in niillims. 
1 
2 
3 
5 
10 
Discharge pressures in niillims. 
of mercury. 
2-34 
1*23 
•84 
•57 
•28 
where the pre.ssures are as 8^4 : 4-4 ; 3 : 2 : 1. 
And at the minimum discharge potentials, which are again constant, 420 volts, the 
readings given are : 
Distance between electrodes 
in millims. 
1 
2 
3 
5 
10 
Discharge pressures in niillims. 
of mercui'y. 
5-02 
2-52 
1-G3 
1-07 
•510 
Special attention is directed to these latter results, inasmuch as the exactness of 
the ratio indicated by the pressures is veiy remarkalile. The ratios of the pressures 
are practically 10 : 5 : 3^1 : 2 : L, tlie nearest approximation to the numbers demanded 
by Paschen s law which has been shown by any of the comparisons, and this result 
is all the more convincing in that these figures were olitalned at tlie critical points, 
where, in the other two gases, the results obtained indicated the law in a somewhat 
less marked degree. 
ihough it would appear that further evidence was unnecessary, the table of 
products was again calculated and is given in Table VI, Also the cori'esponding 
curve is shown in fio’. 7. 
3 H 
VOL, COT,—A, 
