ELECTRIC DISCHARGE WITH THE CHLORIDE OP SILVER BATTERV. 
115 
INDEX TO PART III. 
PAGE. 
91-94 
77 
89 
94-96 
89 
Air—Phenomena of arc in 
Potential necessary to prodnce discharge between discs in 
Arc, Electric—Phenomena of, in air between points, Plate 8, figs. 1-10 .. 
,, in air between spherical surfaces, Plate 10, figs. 1-18 
,, in carbonic acid, Plate 10, figs. 20-23 
„ in hydrogen, Plate 8, figs. 11-19 
„ „ between spherical surfaces, fig. 84, A, B, C, D, E, P, 
G, H . 
,, ,, between points, Plate 8, figs. 21-29; 34-35; Plate 
10, figs. 25-26 
Temperature of, supposing the sudden dilatation of a gas when a discharge occurs 
to be solely due to development of heat 
Carbonic Acid—Phenomena of arc in, Plate 10, figs. 20-23.. 
Potential necessary to produce a discharge in 
Condensation, none occurs in a gaseous medium in contiguity with charged terminals, fig. 74 .. 
Curves representing the potential necessary to produce a discharge in gases 
De La Rive on the nature of the stratified discharge 
Dilatation of gases when discharge takes place is mainly due to a projection of molecules and not 
to increase of temperature 
„ of gases (expansion) the same at both terminals, Plate 10, fig. 24 
,, „ none previous to the discharge in contiguity with charged terminals, fig. 74 
„ sudden, of a gaseous medium when a discharge takes place, fig. 81; Plate 9, 
figs. 8-10 . 85-86 ; 91; 94; 96; 98-99 
Discharge between points in air with a constant potential, and different distances and pressures 91-93 
„ dark, extent of, Plate 9, fig. 4 
Electrometer, the quadrants charged to the same potential but of opposite signs; the needle with 
the potential to be measured (Mascart’s arrangement).. 
Electro-motive force, table of, in volts, necessary for various striking distances in centimetres in 
air between discs at atmospheric pressure 
Expansion. See Dilatation. 
Hydrogen, potential necessary to produce a discharge in 
„ phenomena of arc in .. .. . . .. . . . . . . .. 88; 96 
Hyperbolic curve represents the experimental results of the potential necessary to produce a 
discharge between discs at a constant distance and various pressures in 
air, hydrogen, and carbonic acid 
,, ,, also holds good for a constant pressure and various distances, fig. 78 . . 
Illumination of negative terminals, extent of, dependent on amount of current, Plate 10, figs. 
27-28. 
Mas cart, Pi’ofessor 
Pencil, blacklead-line resistance, use of in determining a tube-potential during a discharge 
Potential, difference of, between terminals during a discharge in a vacuum tube (tube-potential) 
„ necessary to produce a discharge in air 
,, ,, ,, „ carbonic acid.. 
). » „ „ hydrogen. 
Q 2 
97 
99-100 
84-87 
89 
78 
75-76 
70-71; 74 
113 
87-88 
101 
75-76 
108 
111 
83 
78 
98-99 
77; 81 
82 
107-108 
75; 111 
110 
93 
75-77 
78 
78 
