The drug store near my house doesn't sell 35mm film any more. I'm afraid that this trick will die soon.

I went to 12 years of Catholic school, and Father Photius is the coolest priest that I have ever met.

Sorry folks, after reading this thread, I have to jump in here with my suggestion for ignoring the cannister rocket and jumping right into making a good old fashioned potato gun....just google it....not a magic trick but stuns just the same. Look at it as your closer for a picnic or other outdoor venue..... Trust me, they work and you can make one for under twenty dollars worth of PVC pipe, some adhesives, a camping lantern flint lighter and some colorful paint.....five pounds of good old Idaho bakers and a can of hair spray will please the kids (and parents) for a good half hour! I've watched 70-year old men and 10 year old kids giggle till silly with this thing....but a word of caution, build it per specs and check with your local authorities before firing one. But if you want the kid in you to come back, make one of these and have fun with it!!!! Bob

Hey Bob1Dog
How about those pumpkin launching competitions that they have in southern Delaware in October.

Yeah Al, Punkin' Chunkin' !! It made national TV a year or so back, but I've never been to one. It's pretty big sport though; some folks spend a fortune in time and money on their machines to launch a pumpkin farther than any pumpkin has ever gone before. Just like an NFL game, I'd rather watch it on TV rather than fight the crowds. Bob

If you want canisters for seltzer rockets, here is a good website: http://www.teachersource.com/Energy/Ener......ers.aspx

I do a whole chemistry magic show for my class, with the releasing of a genii from a bottle, ping pong poppers, hydrogen balloon bombs, a methanol flame in a bottle that looks really cool in a dark room, to a puking pumpkin to a self carving pumpkin where the face blows out revealing eyes, nose and mouth. Pretty cool overall....

If want to know details, let me know. I also have an extensive thing that I do with the rockets for my class, big lab. If you are interested in that sort of thing as well, please let me know.

Mike

Mike, I wish I had a chemistry teacher like you in 1963 when I flunked my first semester of H.S. chemistry and took earth science instead (which turned out to be a pretty cool course)....bob

don't painc these work just cut the hingen on the lid.
http://www.sugarstand.com/sc/sc0041-m-m-mini-tubes.htm

Years ago, when Coca Cola was bottled in one liter glass with an aluminum, screw on cap, my brother and I would put a couple of ounces of hot water into an empty bottle, drop in a chunk of dry ice and screw on the top - then take cover! After several moments, the top would shoot off into the sky with a 20 foot trail of water behind it. This sounded like a shot gun when the cap's threads finally gave way.

The experiment was a bit dangerous, but not because of the bottle. As a matter of course, these were drop tested, fully filled from 10 feet over a concrete block.

Ah, to be young and foolish... Two words that inevitably go together.