arr and Mado waited in respectful silence while their host made effort to control his feelings.
"Now," he said, after a moment, "I can talk. You have many questions to ask, I know. So have I. But first I must tell you that Carli's was an expedition to your own worlds. A grave danger hangs over them and he was sent to warn them. He has been lost. Our only space-ship capable of making the journey also is lost. Six Martian years were required to build it, so I fear the warning will never reach your people. Already the time draws near."
"A grave danger?" asked Mado. "What sort of a danger?"
"War! Utter destruction! Conquest by the most warlike and ambitious people in the solar system."
"Not the people of Europa?" asked Carr.
"Indeed not. There is another inhabited satellite of Jupiter, next farthest from the mother planet. Ganymede, you call it. It is from there that these conquerors are to set forth."
"Many of them?" inquired Mado.
"Two million or so. They're prepared to send an army of more than a tenth of that number on the first expedition."
"A mere handful!" Carr was contemptuous.
"True, but they are armed with the most terrible of weapons. Your people are utterly unprepared and, unless warned, will be driven from their cities and left in the deserts to perish of hunger and exposure. This is a real danger."