Associated cases of Current and Static Effects. 93 
tact was continued, and then gradually diminished to nothing. 
Thus the record o showed that the wave of power took time in 
the water wire to reach the further extremity; by its first faint- 
ness, it showed that power was consumed in the exertion of lat- 
eral static induction along the wire; by the attainment of a max- 
imum and the after equality, it showed when this induction had 
become proportionate to the intensity of the battery current; by 
its beginning to diminish, it showed when the battery current 
was cut off; and its prolongation and gradual diminution showe 
the time of the outflow of the static electricity laid up in the 
wire, and the consequent regular falling of the induction which 
ad been as regularly raised. 
With the pens m and 0, the conversion of an intermitting into 
a continuous current could be beautifully shown; the earth wire, 
by the static induction which it permitted, acting in a manner 
analogous to the fly-wheel of a steam-engine or the air-spring of 
apump. ‘Thus, when the contact key was regularly but rapidly 
depressed and raised, the pen m made a series of short lines sepa- 
rated by intervals of equal length. After four or more of these 
had passed, then pen o, belonging to the subterraneous wire, be- 
gan to make its mark, weak at first, then rising toa maximum, 
but always continuous. If the action of the contact key was 
less rapid, then alternate thickening and attenuations appeared in 
the o record ; and if the introductions of the electric current at 
the one end of the earth wire were at still longer intervals, the 
records of action at the other end became entirely separated from 
each other ; all showing most beautifully how the individnal 
Current or wave, once introduced into the wire, and never ceas- 
ing to go onward in its course, could be affected in its intensity, 
ls time and other circumstances, by its partial occupation in 
static induction. 
Sustained by its length and the battery, in the same condition 
which is given to pr short wire for a moment by the Leyden 
Scharge (p. 90); or, for an extreme but like case, to a filament 
of shell-lac having its extremities charged positive and negative. 
