Still undecided, he thrust open the door. With a startled gasp he stopped short. Somehow the Venerian had freed himself; at that moment he leaped toward Parkinson.
Instinctively the bacteriologist flung up his hand in a defensive attitude. The onrushing Venerian caught Parkinson's out-thrust fist in the pit of his stomach, and doubled up in pain. While he was thus defenseless, Parkinson placed a well-directed blow on the side of the Venerian's jaw, a blow carrying every ounce of his strength.
So great was the force of the punch, that it lifted the man from Venus and cast him headlong upon the floor. His head landed with a sickening thud. Unmoving, he lay where he had fallen.
Parkinson knelt over him for a moment, then arose. Without question, the man was dead. The Venerian had solved the bacteriologist's last problem; he was free to return to the United States with his means of saving mankind.
rawing the little metal cylinder from his pocket, he burned the body of the Venerian leader to a heap of ashes, ridding the world of the last invader. Then he turned and entered the glass-lined operating room.
Following the dictates of his Venerian knowledge, he crossed to one of the walls, and drew therefrom a flat, glass vessel, somewhat like a petri dish. This contained bacteria that were harmless in themselves, and were hostile to those of the Gray Plague. These germs, brought from Venus, were the only cure for the terrible disease.[1]
[1] The work of the English bacteriologist Twort, in 1915, and the Frenchman, d'Herelle, in 1917, brought to the attention of the scientific world the fact that many bacteria are subject to attack and destruction by some unknown active agent with which they are associated in infected material. This agent, whatever its character, changed growing germ cultures to a dead, glassy substance.
Twort advanced the thought that the agent might be a living, filtered virus, although he favored the theory that it was an enzyme derived from the bacteria themselves.