Our rocket club (SMASH) along with the Ann Arbor rocket club (HUVARS) made a trip to the Detroit Science Center today to see the "Star Trek" exhibit. We all had an enjoyable time looking at that exhibit and all of the other regular exhibits. Peter and I even got a behind the dome look at the planetarium. The dome is made of perforated aluminum. (Oooh! Transparent Aluminum!)

After thoroughly enjoying the museum, we decided to take a side trip to Commonwealth Displays, a store that sells fireworks and cool model rocket stuff. After buying 300 feet of 200 lb tensile strength braided Kevlar line and other rocket building supplies, I notice a "Big Bang Cannon" along with metal tubes of "Bangsite" Bangsite is a trade name for calcium carbide. Calcium carbide reacts with water to make acetylene gas and lime. Acetylene burns with a bright hot flame and is now mainly used for welding. Calcium carbide once was regularly used in miner's lamps. A small water tank dripped water on the carbide. The acetylene generated was directed through a pinhole sized nozzle and burned for illumination. Lamps were also used for auto and bicycle headlamps and even home lighting.

In a Big Bang Cannon a small amount of Bangsite was dropped into water in a chamber at the end of the barrel. The acetylene formed was ignited by a push rod that rubbed against a lighter flint inside the gun barrel whereupon a satisfying "Bang!" was produced, sometimes with fire and smoke.

Anyway the two dozen tubes of bangsite had been sitting on their shelf for twenty years. "Was I willing to buy it, cheap?"

I now own two dozen tubes of Bangsite. My inner child is very pleased.