of atmospheric electricity is subject to marked retardation in its development, so that the quantity of living substance in insulated vegetation is from thirty to fifty per cent, less than the production in free air.
"The transformation of chlorophyllic protoplasm into glucose, etc., appears particularly influenced by atmospheric electricity.
"Flowering and fruit-bearing are subject equally to modification. Electricity does not appear to favor the direct combination of the nitrogen of the air with oxygen, nor with the hydrocarbons of the soil; but it exercises a remarkable influence on the nitrification of the nitrogenized matters of the soil by the intervention of the plant as an electrical conductor. Atmospheric electricity is, therefore, a preponderating factor in vegetable production."
These considerations induced the writer to carry out a series of experiments to ascertain the effect on vegetable development of a surcharge of electricity.
It would appear, from the primary consideration of intensified electrical conditions existing in tropical climates, that the more rapid growth of tropical vegetation might be due to higher electrical force. To the resident in tropical climes such a proposition would be beyond the limits of theory, because of the constant observation of the great development in vegetation during and immediately after a thunderstorm.
The experiments undertaken by the writer gave results that leave no doubt that the growth of vegetation may be enhanced twenty-five to fifty per cent, by the judicious application of electricity.
These experiments consisted in placing upon two marble slabs, one of which was carefully insulated, ten plants of the kind under trial. On the insulated slab was raised an iron structure with depending points, arranged to discharge into the atmosphere surrounding the plants the electricity produced by an induction-machine at an estimated potential of about four thousand to five thousand volts. This arrangement and difference of electrical condition, other conditions being the same, were maintained day and night for eight months, resulting in unmistakable increase in the development of the surcharged plants. The practical application of electricity to the hastening of the development of vegetation is easy. Above the plants or among them may be placed a number of metallic points on a framework insulated from the earth. Wires carried by small balloons—India rubber or collodion bladders filled with gas—to a considerable elevation would collect sufficient of the electricity of the atmosphere, which would be imparted to the points, and these would discharge slowly to the earth, saturating the atmosphere in the neighborhood of the plants. The cost of such an arrangement would be small, and that great advantages are to be obtained from it is undoubted.
