Back in the 1980s, I worked as a paintmaker, in an arts and crafts paint factory. I worked midnights, and one night I was going on a break, and noticed a commotion in the warehouse. The foreman, and the set-up boys had something trapped under a 30' tall storage rack. I went over to investigate, and upon peering underneath the storage rack, I came almost nose-to-nose with an irate mama possum. I also noticed what looked like tiny mice trying to hide near mama's tail. I quickly realized these were little baby possums. Well, the foreman had made elaborate plans to flush the critter from cover, and then beat it to death with canoe paddles (not kidding!). I noticed they had left the side door open, and that it was raining pretty heavily outside. I figured the mama possum had thought "any ol' port in a storm", and had brought her brood into our warehouse for shelter. Anyhow, I couldn't let these idiots beat it to death with canoe paddles. So I ran back to the paintmaking area, and quickly made a solution of 1 part Ammonia Hydroxide, and 9 parts tap water. I brought my concoction back over to the warehouse, in a small bowl, and slid it under the storage rack. I then told everyone to go away, for about fifteen minutes. And fifteen minutes later, the mama possum and youngins had scurried back out the side door. Problem solved! I had to fill out a 'formula sheet' for everything I made. So I filled out one for "anti-possum gas", and filed it in the lab, just as I would for a batch of paint!