"Heat and light travel in waves through the ether. When it is destroyed, only blackness and entire absence of heat remain. Nothing can bear the cold of interstellar space and yet it is warm compared to the absolute cold which the absence of ether produces. When you direct one of these rays toward a Jovian ship, the ether in the ship is destroyed. No insulation against the cold of space will interfere for the ether penetrates and permeates all substance. The cold of absolute nothingness will destroy all life in the twinkling of an eye and the ship will be reduced to a puff of powder. At such a temperature, even stellanium has less strength than the most brittle substance. * * * * * "There are two of these devices, set to different powers. The one with the blue rod is for use against space ships either before or after they enter the atmosphere envelope. Beware of using it except when it points in a direction almost normal to the surface of your planet. These devices tap and use the enormous force of gravity itself and when they are locked to your planet, they are anchored to the center of gravity of the planet. Unless it were normal to the planet's surface, its reactive force is so great that it would disrupt the balance which holds the planet in place were the beam sent off on a tangential line. "The other, whose projecting rod is painted red, can be used at any angle as its force is only a minute fraction of that of the other. It also must be locked to the center of gravity of the earth before it is used by means of the switch on the front. This instrument will give you power to annihilate your oppressors on earth, for while it has not the terrible force of the other, it will penetrate any protective screen which the science of Jupiter can erect. Use it only against the Jovians and when you have finished with it, destroy it that it may not fall into the hands of those who would misuse it. The other may be left intact to repel other Jovian attacks but I think you need fear none. Once they learn you have it, they will be content with their conquests of Venus and Mercury and give you a wide berth. The Jovians have had a taste of it already and they leave Mars alone. Each instrument is set in action by closing the switch on top, after closing the gravity anchor switch. To stop them, open the top switch." Under the direction of the Grand Mognac, the Martians placed the terrible weapons in the transporter prepared for them. Turgan and Damis strove to thank the Grand Mognac for his gift but he interrupted them promptly. "No thanks are due us," he said. "We have done that which we believe is the best for the orderly development of this galaxy of planets and there is no reason why we should be thanked. Now enter the transporters and you will be returned to your space ship. Destroy your oppressors and work for the day when Mars and Earth will march in peace toward the final goal of all life."