There are other properties belonging to the ether more wonderful, if possible, than those already mentioned. Its ability to maintain enormous stresses of various kinds without the slightest evidence of interference. There is the gravitational stress, a direct pull between two masses of matter. Between two molecules it is immeasurably small even when close together, but the prodigious number of them in a bullet brings the action into the field of observation, while between such bodies as the earth and moon or sun, the quantity reaches an astonishing figure. Thus if the gravitative tension due to the gravitative attraction of the earth and moon were to be replaced by steel wires connecting the two bodies to prevent the moon from leaving its orbit, there would be needed four number ten steel wires to every square inch upon the earth, and these would be strained nearly to the breaking point. Yet this stress is not only endured continually by this pliant, impalpable, transparent medium, but other bodies can move through the same space apparently as freely as if it were entirely free. In addition to this, the stress from the sun and the more variable stresses from the planets are all endured by the same medium in the same space and apparently a thousand or a million times more would not make the slightest difference. Rupture is impossible. Electric and magnetic stresses, acting parallel or at right angles to the other, exist in the same space and to indefinite degrees, neither modifying the direction nor amount of either of the others. These various stresses have been computed to represent energy, which if it could be utilized, each cubic inch of space would yield five hundred horse-power. It shows what a store-house of energy the ether is. If every particle of matter were to be instantly annihilated, the universe of ether would still have an inexpressible amount of energy left. To draw at will directly from this inexhaustible supply, and utilize it for the needs of mankind, is not a forlorn hope. The accompanying table presents these contrasting properties for convenient inspection. CONTRASTED PROPERTIES OF MATTER AND THE ETHER. MATTER. ETHER.