Two Timer

By FREDRIC BROWN

Illustrated by STONE

Experiment

"The first time machine,gentlemen," ProfessorJohnson proudlyinformed his two colleagues."True, it is a small-scale experimentalmodel. It will operateonly on objects weighing lessthan three pounds, five ouncesand for distances into the pastand future of twelve minutes orless. But it works."

The small-scale model lookedlike a small scale—a postagescale—except for two dials in thepart under the platform.

Professor Johnson held up asmall metal cube. "Our experimentalobject," he said, "is abrass cube weighing one pound,two point three ounces. First, Ishall send it five minutes into thefuture."

He leaned forward and set oneof the dials on the time machine."Look at your watches," he said.

They looked at their watches.Professor Johnson placed thecube gently on the machine'splatform. It vanished.

Five minutes later, to the second,it reappeared.

Professor Johnson picked itup. "Now five minutes into thepast." He set the other dial. Holdingthe cube in his hand he lookedat his watch. "It is six minutesbefore three o'clock. I shall nowactivate the mechanism—byplacing the cube on the platform—atexactly three o'clock. Therefore,the cube should, at fiveminutes before three, vanish frommy hand and appear on the platform,five minutes before I placeit there."

"How can you place it there,then?" asked one of his colleagues.

"It will, as my hand approaches,vanish from the platformand appear in my hand tobe placed there. Three o'clock.Notice, please."

The cube vanished from hishand.

It appeared on the platform ofthe time machine.

"See? Five minutes before Ishall place it there, it is there!"

His other colleague frowned atthe cube. "But," he said, "whatif, now that it has already appearedfive minutes before youplace it there, you should changeyour mind about doing so and notplace it there at three o'clock?Wouldn't there be a paradox ofsome sort involved?"

"An interesting idea," ProfessorJohnson said. "I had notthought of it, and it will be interestingto try. Very well, Ishall not ..."

There was no paradox at all.The cube remained.

But the entire rest of the Universe,professors and all, vanished.

Sentry

He was wet and muddy andhungry and cold, and he wasfifty thousand light-years fromhome.

A strange blue sun gave lightand the gravity, twice what hewas used to, made every movementdifficult.

But in tens of thousands ofyears this part of war hadn'tchanged. The flyboys were finewith their sleek spaceships andtheir fancy weapons. When thechips are down, though, it wasstill the foot soldier, the infantry,that had to take the ground andhold it, foot by bloody foot. Likethis damned planet of a star he'dnever heard of until they'd landedhim there. And now it wassacred ground because the alienswere there too. The aliens, theonly other intelligent race in theGalaxy ... cruel, hideous and repulsivemonsters.