32 
POPULAR SCIENCE REVIEW. 
recent experimenters, and the account of whose researches is 
given in the Comptes Rendus for the present year, found that 
when a current from a galvanic battery was passed through the 
leaves, no^result was produced and that the plant did not respond 
to the stimulus. On the other hand, when in place of the direct 
an indirect current was employed, by the use of a small Ruhm- 
korff’s coil, the results were entirely different — the leaflets folded 
up and the leafstalks drooped along the whole course of the stem. 
If the current were continued for a short time the plant after a 
period of repose raised its leaves and resumed its ordinary state ; 
but if the experiment were prolonged for twenty-five minutes 
the organism seemed to become entirely exhausted, and the 
following day was found withered and blackened, as though 
struck by lightning, and the same effect has been noticed by 
M. Bert. Still more remarkable were the effects noticed when 
the plant was allowed to come in contact with the vapour of 
ether. Induction currents of electricity have little or no effect 
on animals when under the influence of anaesthetic agents. In 
order to see what would be the effect in the case of the Mimosa, 
under like circumstances, M. Blondeau exposed a specimen to 
the anaesthetic effect of a few drops of ether sprinkled in the 
glass enclosing the plant. In a short time, says M. Blondeau, 
the plant experienced the effect of the anaesthetic — its leaves 
refused to move when shaken, and manifested no sensibility even 
when the induction current was passed through them. 
From what has been stated it will be evident that Ave have 
yet much to learn as to the causes of the movements observable 
in the vegetable world. Different plants act differently under 
the same circumstances, as in De Candolle’s experiments with 
artificial light. The Mimosa and the Oxalis so treated gave 
opposite results. So, too, the same plant at various times and 
under diverse conditions acts differently. In no other way can 
we account for the discrepancies in the results of experiments 
conducted by men of equal ability and competence. It is pro- 
bable that some of these discrepancies may arise from the con- 
founding the movements that constitute the so-called sleep of 
plants with those that take place in consequence of some external 
stimulus. This seems the more likely from a consideration of 
the researches recently made public by M. Paul Bert.* We 
regret that our space does not permit us to allude at length to 
M. Bert’s elaborate paper, but we may, by way of conclusion, 
* M. Bert’s paper only reached us while this sheet was passing through 
the press. It is contained in the 4th volume of the Memoires de la Societe 
des Sciences Physiques et Naturelles de Bordeaux, and is dated April, 1867,. 
the title-page of the cahier ” in which the paper appears hearing the date 
1866 ! It is one of the most important memoirs on the subject of the Sensi- 
tive plant that has yet been issued, and should be consulted by all interested 
in the matter. 
