d be, if that were possible, to detect and
measure the actual response of the organism to a definite testing blow.
When an animal receives an external shock it may answer in various ways;
If it has voice, by a cry, if dumb, by the movement of its limbs. The
external shock is the stimulus, the answer of the organism is the
response. If we can make it give some tangible response to a questioning
shock, then we can judge the condition of the plant by the extent of the
answer. In an excitable condition the feeblest stimulus will evoke an
extraordinarily large response, in a depressed state even a strong
stimulus evokes only a feeble response, and lastly, when death has
overcome life, there is an abrupt end of the power to answer at all.

Prof. Bose then explained the principle and action of his apparatus by
which the plant attached to it is automatically excited by successive
stimuli which are absolutely constant. In answer to this the plant makes
its own responsive records, goes through its own period of recovery, and
embarks on the same cycle over again without assistance from the
observer at any point. In this way the effect of changed external
conditions is seen recorded in the script made by the plant itself.

It has been thought that plants like mimosa alone were sensitive. But
Sir J. C. Bose's apparatus demonstrated the unsuspected fact that every
plant and every organ of every plant answered to a shock by a
contractile spasm, as by an animal muscle. If perception of feeble
stimulus be taken as a measure of ascent in the scale of life then the
superiority of man must be established on a foundation more secure than
sensibility. The most sensitive organ by which we can detect electric
current is our tongue. An average European can perceive a current as
feeble as six micro-amperes, a micro-ampere being a millionth part of
the electric unit. Possibly the tongue of a Celt is more excitable, and
I have no doubt that my countrymen can easily boast the Celt in this
particular test. But the plant mimosa is ten times more excitable than
the tongue of an advocate in this province.

Professor Bose then showed how identical were the effects of light,
warmth and various drugs on the plant and animal. These experiments
bring the plant much nearer than we ever thought. We find that it is not
a mere mass of vegetative growth, but that its every fibre is instinct
with sensibility. We are able to record the throbbings of its pulsating