Challenge: One shot glass is filled with water and the other with whisky.
The challenge is to get the whisky in the glass that has the water and the water in the glass that has the whisky without using any other containers including your mouth.
Preparation: You need
Two identical shot glasses
One non porous piece of paper, like a playing card. A plastic card such as gift voucher or driving licence could also be used
Water and your choice of spirit.
Solution: Place the non porous paper ( playing card ) on top of the shot of water.
Turn the card and the water shot glass round carefully.
The paper will stay attached to the shot glass easily.
Now place the water shot glass and card, still upside down, on top of the shot of bourbon. Slowly and carefully, pull the playing card just far enough out to make a small opening between the two glasses. Water, being heavier than alcohol, will flow into the whisky glass and displace the whisky into the water glass.
You have just made the switch
If you are truly skilled at this bar trick, you will be able to replace the paper between the two shot glasses and remove the whisky and put it back on the bar.
Please make sure that the opening between the glasses is very small as a large opening will cause the water and alcohol to mix.