The lecturer had succeeded in devising experimental methods and apparatus by which the plant was made to give an answering signal, which was then automatically recorded into an intelligible script. The results of the new investigations were so novel that Professor Bose spent several years in perfecting automatic instruments which completely eliminated all personal equations. The plant attached to the recording apparatus was automatically excited by a stimulus absolutely constant, making its own responsive records, going through its period of recovery, and embarking on the same cycle over again without assistance at any point from the observer. The most sensitive organ for perception of a stimulus was the human tongue. An average European could by his tongue detect an electrical current as feeble as six micro-amperes, a micro-ampere being a millionth part of a unit of electrical current. Professor Bose found that his Hindu peoples could detect a much feebler current, namely, 1.5 micro-amperes. It was an open question whether such a high excitability of the tongue was to be claimed as a distinct advantage. But the fact might explain the eminence of his countrymen in forensic domains! (Laughter.) The plant, when tested, was found to be ten times more sensitive than a human being. EFFECT OF FOOD AND DRUGS It was shown that when the plant had a surfeit of drink, it became excessively lethargic and irresponsive. By extracting fluid from the gorged plant, its motor activity was at once re-established. Under alcohol its responsive script became ludicrously unsteady. A scientific superstition existed regarding carbonic acid as being good for a plant. But Professor Bose's experiments showed distinctly that the gas would suffocate the plant as readily as it did the animal. Only in the presence of sunlight could the effect be modified by secondary reaction. AUTOMATISM AND GROWTH It was impossible in a limited space, said Professor Bose, to do more than mention the numerous other remarkable experiments which riveted the attention of the audience. By means of apparatus specially devised, pulsative plants were made to record their rhythmic throbbings. It was shown that the pulse beats of the plants were affected by the action of various drugs, and divers stimuli, in a manner similar to that of the animal heart. Perhaps the most weird experience was to watch the death-struggle of a plant under the action of poison. Turning from death to its antithesis life and growth, the audience were shown how the latter was made visible by means of the appliances invented by Professor Bose. The infinitesimal growth of a plant became highly magnified in the experiment. RESEARCHES AT PRESIDENCY COLLEGE