We're Off to Mars!

Finally, Joe opened the package. He merely inserted his thumb into a conspicuous slot at the corner and pushed it around the top edges. The silver-gray material parted easily and the lid came off the package. As it fell aside, he saw that the interior was filled with what resembled a rubber sponge soaked in black lacquer. It was dry, springy, and blackly glistening. He clutched at it and pulled it out.