studied the effect of an electric and a
magnetic field on Avena coleoptiles when they were mounted on a
klinostat. They mounted one metal plate above the coleoptile and one
around its base. These plates were separated by 1.75 centimeters and
charged with a direct current power supply. Plate voltages ranging from
500 to 2500 volts, applied longitudinally to the coleoptile, caused a
significant increase in elongation and was independent of apical plate
polarity.