inconvenient and tedious process of photography (which again introduced
complications by subjecting a plant to darkness and thereby modifying
its normal excitability); and the plant was not automatically excited by
stimulus, besides the results obtained were liable to be influenced by
personal factor. So Dr. Bose set about the invention of an apparatus,
which should discard the use of photography and in which the plant
(attached to the recording apparatus) should be automatically excited by
stimulus absolutely constant, should make its own responsive record,
going through its own period of recovery, and embarking on the same
cycle over again without assistance at any point on the part of the
observer. Great difficulties were encountered in realising these ideal
requirements. They appeared, at first, to be insurmountable. But, with
continuous toil and persistence, Dr. Bose succeeded in designing a long
battery of supersensitive instruments and apparatus, which made the
seeming impossible possible. His ingenious "Resonant and Oscillating
Recorders" gave a simple and direct method of obtaining the record. The
plant, being automatically excited by stimulus, made its own responsive
record. The closed doors, at last, opened. The secret of plant life
stood revealed by the autographs of the plant itself. The great
_sadhana_ of his life now received its fulfilment. "It has been
beautifully said--and it is a law of the moral world as unchangeable as
physical laws--'Ask, and it shall be given you; seek, and ye shall find;
knock, and it shall be opened unto you; for every one that asketh
receiveth; and he that seeketh findeth and to him that knocketh it shall
be opened."[24]

TRANSMISSION OF EXCITATION IN MIMOSA

Dr. Bose had shown that all plants are sensitive--that there is no
difference between the so-called 'sensitive' and the supposed
'non-sensitive'--that they gave alike the true excitatory _electric
response_ as well as _motile response_. The evidence of plant's script
now removed beyond any doubt the long-standing error which divided the
vegetable world into 'sensitive' and 'insensitive.' There remained,
however, the question of nervous impulse in plants, the discovery of
which, though announced by Dr. Bose, ten years ago, did not yet find
full acceptance.

Finding that the scope of his investigation has been very much enlarged
by the devise of the Resonant Recorder, Dr. Bose proceeded to attack the
_current_ view "th