172 
MESSRS. W. DE LA RUE AND H. W. MULLER ON THE 
sphere), 2400 rod cells, (C. *) 0 , 014210 W. Discharge agitated, the strata 
about 0*5 inch apart. 
2. — Pressure 1*2 m.m., 1579 M, 2400 rod cells, (C.) 0-014210 W. Strata in forms 
like the right-hand portion of 59, fig. 46, every now and then assuming the 
tongue-like formation 57, fig 46. 
Fig. 43. 
}u3 c] 
6 . 
~czm a ml 
> 
I4-. 
3. — Pressure 0'2 m.m., 263 M. The current of 1080 powder cells would not pass, 
but that of 1200 rod cells did so, producing strata, and the peculiar dis- 
charge entering the negative ring, as shown at «, fig. 43, (C.) 0 '007631 W, 
with 
200.000 ohms external resistance, 
300.000 „ 
400.000 „ 
500.000 „ 
600.000 „ 
700,000 „ 
(C.) 0 '00341 4 W, there were 25 strata 
(C.) 0'002675 W, „ 24 „ 
(C.) 0-002200 W, „ 23 „ 
(C.) 0-001866 W, „ 22 „ 
(C.) 0-001622 W, „ 21 „ 
the current would not pass, 
with 3,600 cells and, 
6,500,000 ohms 
(C.) 0"000567 W, there were still 21 
strata. 
4. — The exhaustion was carried still further, but as we did not at that time 
possess the McLeod gauge, which has been more recently attached to the 
* C, when within brackets indicates that the value of the current, given in Webers, was obtained 
approximately by calculation ; when not within brackets it indicates that the current was directly observed. 
