io Electricity and Magnetic. 261 
Fig. 8. 
the influence of the primary, its separate induction will be 
rendered manifest by the effects on helix No. 1. When the 
handles < 2 , h are grasped a powerful shock is received, pro- 
ving the induction of a tertiary current. 
80. By a similar but more extended arrangement, as shown 
in fig. 9, shocks were received from currents of a fourth and 
fifth order ; and with a more powerful primary current, and 
additional coils, a still greater number of successive induc- 
tions might be obtained. 
81. The induction of currents of different orders, of suffi- 
cient intensity to give shocks, could scarcely have been anti- 
cipated from our previous knowledge of the subject. The se- 
condary current consists, as it were, of a single wave of the 
natural electricity of the wire, disturbed but for an instant by 
the induction of the primary ; yet this has the power of in- 
ducing another current, but little inferior in energy to itself, 
and thus produces effects apparently much greater in propor- 
tion to the quantity of electricity in motion than the primary 
current. 
82. Some difference may be conceived to exist in the ac- 
tion of the induced currents, and that from the battery, since 
they are apparently different in nature; the one consisting, 
as we may suppose, of a single impulse ; and the other of a 
succession of such impulses, or a continuous action. It was 
therefore important to investigate the properties of these cur- 
rents, and to compare the results with those before obtained. 
83. First, in reference to the intensity, it was found that 
with the small battery a shock could be given from the cur- 
rent of the third order to twenty-five persons joining hands ; 
also shocks perceptible in the arms were obtained from a cur- 
rent of the fifth order. 
84-. The action at a distance was also much greater than 
could have been anticipated. In one experiment shocks from 
the tertiary current were distinctly felt through the tongue, 
