Doubtless you would like to have at home the experience of firing a cannon, of hearing a report loud enough to frighten nervous persons, to see the shell fly as quick as lightning, and then to witness the recoil of your home-made piece of artillery.
Your apparatus will be quite simple, for you must first take a strong bottle, such as a vinegar, or better still, a champagne bottle, and fill it a third full with water.
Next take a little carbonate of soda, and also some tartaric acid, both of which may be obtained at any druggist’s, taking care to wrap them in packets which will not be confused one with the other.
Dissolve the carbonate of soda in the water contained in the bottle, at the same time placing the tartaric acid in a playing card rolled in the form of a cylinder, one end of which should be filled with a plug of blotting-paper.
Fig. 21.—The bottle cannon.
Having accomplished this much to your satisfaction, suspend the cartridge just made from the cork of the bottle by sticking in it a pin to which is attached a thread, particular care being taken that the bottle is standing upright on the table, and that the open end of the tube is the upper one.
After having regulated the length of the thread so that the bottom of the tube does not touch the liquid in the bottle, tightly fit the cork in.
You now have your cannon charged, and all that remains to be done is to fire it.
This is done by laying the bottle horizontally on two pencils placed parallel to one another, thus forming a gun-carriage. Immediately the bottle is so placed, the water penetrates the tube, and dissolves the tartaric acid. The carbonic acid gas which is immediately produced blows out the cork with a violent explosion, whilst at the same time, owing to the reaction, the bottle rolls back on the two pencils, in exact imitation of the recoil of a piece of artillery ([Fig. 21]).