Lost Race of Mars Author:Robert Silverberg Are the Old Martians really a lost race-just withered mummies lying in dark caves? Or are they still alive-somewhere on the red planet? — Sally and Jim must find out. They must help their father discover if the Old Martians still exist. His work as a scientist is at stake! — But it's not easy. They are the only visitors to the Mars colony in this... more » year 2017. And no one really wants them there.« less