HEART-BEAT OF A LEAF.

Taranaki Daily News, 13 March 1920, Page 11

HEART-BEAT OF A LEAF.

MEASURING PLANTS' DEATH SPASMS. In the Reading Room at the India Office, Whitehall, R.W., before a lar<»e audience, Sir Jngadis Chandra Rose, a savant who, by means of delicate instruments lie has invented, has made some remarkable discoveries in the analogy between plants and animals, gave a demonstration of his work. '■' There is a pulsation in certain plant tissues which with animals is heartbeat," he said. "Identical effects are caused by stimulants and poisons in animals and vegetables, and in the death spaam which occurs in both.' 1

Referring to the difficulty in recording these "incessant throbbing?" ;n the apparently perfectly still plant, he stated that "the sluggish movement of a snail is* about fiOO'u times faster than the movement of growth in a plant, the average rate of which is one millionth part of an inch per second." The civscograph (the name ;,f his invention.) \vo:ild show the sua'! moving with a speed of 21)9,000,000 feet per hour.

Sir Jagadis, having graphically described his vast magnification, picked a leaf from a po t plant, of cyclamen and placed it on the magnetic needle of the crcscngraph. From the mirror attached to the needle a spot of light appeared at once on the screen, and moved backwards and forwards across the latter at a rate of 10 feet in 12 seconds.. The actual rate, of the plant's pulsation was 100,000 th part of an inch per second. When the leaf was stimulated with an electric current the pulsation and the spot of light were quickened. "There is nothing in the animal which has not been forestalled in the plant," said the lecturer "When a plant is placed in unhappy conditions, as in a hath of hot water, the time comes when it struggles and dies, and its struggles are the same as in the animal."