The Professor explained next other experiments which he had performed on
plants and whose results had exhibited the close parallel which plant
life bears to human life. With the aid of another delicate instrument he
showed how the growth of plants can be influenced by drugs and the
demonstration on the screen of the manner in which the slow growth of a
plant can be thus expedited was one of extraordinary interest. One was
able to see the flame of life moving up the screen and recording at
intervals the stages of growth, a lengthening of the intervals between
each recorded glow illustrating the acceleration of growth as soon as
the drug was applied. The instruments necessary to record this
phenomenon are of extraordinary delicacy, and barely survived the strain
of the journey from Calcutta.