Sensitivity of vegetable kingdom

Sitting on a bench, the Master spoke about the sensitivity of the vegetable kingdom:

Although sensitivity in plants is slight as compared with that manifested in animals, within their own kingdom they have sensitivity and vegetable spirit. Cut across a conical shape, sprinkle a little sulphate of copper on it, add a little water and then observe it with a magnifier. You will find its components rushing toward the center. Their sensitivity is apparent in their effort to reach the center until they form a cylinder.