34 M. C. Blondeau on the Irritability of Plants. 
current produced by means of a very small Ruhmkorff’s coil. 
The results were then quite different. Scarcely had the cur- 
rent begun to pass, when the leaflets were seen to apply them- 
selves to one another, then the petioles were depressed along 
the stem, and the movement was rapidly propagated from one 
end of the plant to the other. According to this result, the 
plant is sensitive to electrical disturbances, and behaves in 
this respect exactly like animals. 
We wished to ascertain whether the subjection of the plant 
to electricity for a longer or shorter time would produce in it 
phenomena worthy of notice; and with this view we caused 
the induction-current to act upon three of our Sensitive Plants 
during different periods of time. The first plant submitted to 
experiment received for five minutes the disturbances produced 
by the Ruhmkorff’s coil, and at the end of this time it was left 
to itself. or more than a quarter of an hour the plant re- 
mained in the state of prostration to which it had been reduced 
by the electrical action; but by degrees the leaflets opened, 
and the stalks raised themselves again, and in about an hour 
the plant had regained its original position, and did not appear 
to have suffered in the least by the shocks to which it had been 
subjected. 
i second Sensitive Plant was subjected to the same treat- 
ment, but continued for ten minutes. At the end of this time 
the induction-current which traversed the stem was suspended 
and the plant left to itself. The Sensitive Plant remained in 
the state of prostration to which it had been brought by the 
action of the current for more than an hour, and it was only 
after this lapse of time that the leaflets began to open and the 
petioles to elevate themselves. This movement moreover took 
pe more slowly and laboriously than in the preceding case. 
vidently the plant had been fatigued ; for it did not return to 
its original position until two hours and a half after the current 
had ceased to traverse it. 7 
Our third Sensitive Plant was subjected to the action of the 
induced current for five-and-twenty minutes, and then the 
plant was left to itself. In this case we waited in vain for it 
to resume its original Cites : the prolonged electrical action 
had been sufficient to destroy all irritability, and even to cause 
the plant to perish ; for on the following day we found our 
Sensitive Plant withered, and even blackened as if it had been 
struck by lightning. 
Our fourth Sensitive Plant was reserved for an experiment 
which has proved to us that electrical disturbance acts upon 
plants in the same way as upon animals. 
We know that man, as well as the other animals, when sub- 
