[Sir J. C. Bose has recently invented the "Magnetic" crescograph. It is
a supersensitive instrument and the very high magnification obtained by
it surpasses all existing appliances. By this instrument, phenomena
hitherto beyond the reach of investigation can now be studied with great
precision. It shows ultra-microscopic changes inducted in a growing
organism even by a puff of smoke or a gentle breeze, by a passing cloud
or fleeting brightness. This super magnifier was exhibited for the first
time by Sir J. C. Bose before an appreciative gathering 10-1-1919. A
number of lady students, professors, lawyers, doctors and several
eminent personages gathered to hear the great Indian scientist.]
In his Discourse on the above subject on Friday, Sir J. C. Bose
illustrated how the limitations imposed on the advance of science by the
imperfection of our senses, may stimulate the invention of
supersensitive apparatus which reveals to us the existence of phenomena
hitherto unknown. Thus the invention of the microscope from a simple
lens magnifying 3 or 4 times into progress up to 1500 diameters has
given birth to new sciences. But still higher magnification is demanded
in unravelling the mystery of movements associated with the simplest
type of life as seen in plants. Greatest potentiality in life is often
latent; the gigantic banian tree grows out of a thing which is smaller
than the mustard seed. Within the seed-coat the dormant life remains in
safety, protected from dangers outside. The seeds may thus be subjected
without harm to cold so intense as will freeze mercury into solid and
air into liquid. Winds and hurricanes scatter the seed of life and the
cocoa-nut rides the tumultuous waves till anchored safe in an island
yet to be inhabited. In due season there begins a series of most
astonishing transformations; the latent life wakens, and the seedling
begins to grow. The root turns downwards and the shoot upwards.
Underground, the root winds its way round stones and obstacles towards
moist places. Above ground the stem bends as if in search of light.
Tendrils twine about a support. These visible movements are striking
enough, but within the unruffled exterior of the plant body there are
others, energetic and incessant, which escape our scrutiny. The bending
of a growing organ towards or away from stimulus must be due to unequal
growth on two sides of the organ, a retardation of growth on the
proximal or acceleration on the distant sides. Various theories have
been advanced which have proved inadequate. For the identical stimulus
of gravity produces one kind of curvature in the root and the very
opposite in the shoot. The possibility of direct experimental
investigation has been frustrated by the excessive slow rate of growth
rendering accurate measurement impossible.