In the first editions of this book I did not venture to speak about the improvements that could be obtained in agriculture with the aid of electricity, or by watering the soil with cultures of certain useful microbes. I preferred to mention only well-established facts of intensive culture; but now it would be impossible not to mention what has been done in these two directions.

More than thirty years ago I mentioned in Nature the increase of the crops obtained by a Russian landlord who used to place at a certain height above his experimental field telegraph wires, through which an electric current was passed. A few years ago, in 1908, Sir Oliver Lodge gave in the Daily Chronicle of July 15 the results of similar experiments made in a farm near Evesham by Messrs. Newman and Bomford, with the aid of Sir Oliver Lodge’s son, Mr. Lionel Lodge.

A series of thin wires was placed above an experimental field at distances of ten yards from each other. These wires were attached to telegraph poles, high enough not to stand in the way of the carts loaded with corn. Another field was cultivated by the side of the former, in order to ascertain what would be the crops obtained without the aid of electricity.

The poles, five yards high, were placed far away from each other, so that the wires were quite loose. Owing to the high tension of the currents that had to be passed through the wires, the insulators on the poles were very powerful. The currents were positive and of a high potential- about 100,000 volts. The escape of electricity under these accounts was so great that it could be seen in the dark. One could also feel it on the hair and the face while passing under the wires.

Nevertheless, the expenditure of electric force was small, Sir Oliver Lodge writes; because, it the potential was high, the quantity of consumed energy was, notwithstanding that, very small. It is known, indeed, that this is also the case with the discharges of atmospheric electricity, which are terrible in consequences of their high tension, but do not represent a great loss of energy. An oil motor of two horse-power was therefore quite sufficient.

The results were very satisfactory. The wheat crop in the electrified field was, in the years 1906-1907, by 29 to 40 percent greater, and also of better quality, than in the non-electrified field. The straw was also from four to eight inches longer.

For strawberries the increase of the crop was 35 percent, and 25 percent for beetroot.

As to the inoculation of useful microbes by means of watering the soil with cultures of nitrifying bacteria, experiments on a great scale have been made in Prussia upon some peat-bogs. The German agricultural papers speak of these experiments as having given most satisfactory results.

Most interesting results have also been obtained in Germany by heating the soil with a mixture of air and hot steam passed along the ordinary propagate this system, and the photographs of the results published by the Society in a pamphlet, Gartenkultur, Bodenheizung, Klimaverbesserung (Berlin, 1906), seem to prove that with a soil thus heated the growth of certain vegetables is accelerated in some extent.