You meet a lot of screwy people when you do police work. Like the guy who popped up in a murder job. Offered to solve the case with-- Dalrymple's Equation By Paul W. Fairman Illustrated by W. E. Terry [Transcriber's Note: This etext was produced from Imagination Stories of Science and Fantasy June 1956 Extensive research did not uncover any evidence that the U.S. copyright on this publication was renewed.] It's the not knowing that gets you. The wondering. Thinking sometimes one way and sometimes the other. But never knowing for sure. Being suckered is bad enough but _wondering_ whether you've been suckered is rougher. Or whether you've let the biggest thing since fingerprints slide right by you. Someday the case may be solved. Then we'll know for sure--one way or the other--Donovan and I. What case? Wait 'til I tell you. It won't take long. The thing started with as crazy a murder as two Homicide cops ever got called in on. In a bar on Tenth Avenue near Grand--you probably know the place and you probably read about the case. It was in all the papers. But the whole story never saw print. We were rung into it by a call from the squad car boys who got there first. We walked in and a cop I didn't know pointed a thumb at a young guy lying with his head on the bar and said, "Deader than a lamp post for my money." A young lad--around twenty-three or four--lying there as though he'd had one too many and was sleeping it off. He _had_ downed one too many. And he would spend all eternity sleeping it off. He was all through. The barkeep stood there with his apron hanging out and a baffled look on his face. A look that had all the earmarks of being genuine. I said, "Kennedy--Homicide. What happened?" The barkeep shrugged and licked his dry lips. "I dunno. He just keeled over. I got scared and called the cops." The kid certainly looked like a morgue job, as I said, but we don't take things like that for granted. The squad car boys had called General Hospital and now a couple of internes came in with a respirator. They didn't use it, though. One of them put his nose close down to the kid's mouth and then looked at the barkeep. "You served him a drink?" The barkeep nodded. "That's what he came in for." "Let's see the bottle." The barkeep gave that a little thought and then took a bottle off the rack and pushed it over the bar. The interne sniffed it, made a face and said, "There's enough arsenic in there to depopulate New Jersey." "Arsenic!" the barkeep croaked. "You're crazy! We don't serve nobody no arsenic here!" The interne looked at Donovan and me and said, "Call your meat wagon, lads. This one is beyond us."