202 
MESSRS. W. DE LA RUE AND H. W. MtLLER ON THE 
Tube 70, 25 inches between two straight terminals, diameter 1*875 inch. 
Sulphuretted-hydrogen, Pressure not known, the Working Resistance was from 
100,000 to 120,000 ohms. 
181. — With 2160 cells, strata grouped in threes, as 1, fig. 56; on introducing 
2,690,000 ohms the disc-shaped strata were produced, shown in 2, fig. 56 ; 
with 1,600,000 ohms the strata closed up to half the distance apart and 
became unsteady. 
Fig. 56. 
182. — The battery of 2160 cells was connected to the Varley condenser of 
42 ‘8 m.f., a water resistance of 300,000 ohms being in the circuit. As the 
charge ran down after the condenser had been disconnected from the battery, 
a most beautiful series of phases was obtained during the two minutes and a 
half which elapsed before the potential had fallen so low that the current 
ceased to pass. The first phase is shown in 3, fig. 56, consisting of groups of 
three bow-shaped strata with a disc between each group. The next is repre- 
sented in 4, fig. 56 ; this was followed by a series of discs, as 1, fig. 55, these 
gradually became wider apart until there were only eight in the whole 
length of the tube. The discharge afterwards became a rustling luminosity 
and suddenly went out. Any phase could be maintained by replenishing 
the condenser through an adjusted resistance, FR"., fig. 26, Part I. 
183. — By frequently working the tube there was gradually deposited a layer of 
crystalline sulphur on the inside ; at last the tongue-shaped strata could no 
longer be obtained, but it was found that grasping the tube near the negative 
terminal caused their production, 5, fig. 56. Ultimately the tube became dead 
and the current of 8040 cells would not pass. 
Tube 122, Sulphuretted Hydrogen and Hydrogen. 
184. — 3240 cells connected with the condenser. At full tension a beautiful 
