Some information supplied by Tom Lammers and the Atlas/Timely discussion list. On-sale date from 1956 Periodicals, Copyright Office, Library of Congress.
A criminal thinks he has shot a night watchman and goes into suspended animation for forty years so that the police will forget about him, but when he comes out of the suspended animation, he reads in the old newspaper that his partner was the one who wounded the night watchman earlier in the evening and the police never suspected him.
A disgruntled janitor's obsessive effort to create a sweeping robot costs him his job and ends in failure, but only because he sees no use for a perpetual motion machine.