How to make liquid carbon dioxide

Here is a simple way to demostrate that you can create liquid carbon dioxide by increasing the pressure on a sample of dry ice. If you can create a pressure of about 5 atmospheres the solid carbon dioxide will undergo a phase change to a liquid. This is actually pretty easy to do using some dry ice powder, some warm water and a common plastic pipette. This is even more fun if you have someone (wearing goggles for safety) closely observe the transition in the glass up close!