Force Exerted by Growing Plants.
THE force exerted by growing plants can be easily measured. Darwin took a spring clothespin, measured the force necessary to open it, and then fastened it upon the growing root. He found that the pressure was of many ounces. President Clarke of Amherst Agricultural College made some interesting experiments with a growing squash, which was harnessed and had levers attached in such a way that the force exerted could be ascertained. It was equal to thousands of pounds, and finally the harness broke. In a grave-yard at Hanover, Germany, a block of stone containing twenty cubic feet has been thrown out of place by a tree growing from a seed which germinated in the crevice of the rock. It has already been lifted over five inches.—Boston Budget.