Centrifuges can be used to separate emissible liquids into layers based on density. This video demonstrates the proper use of a centrifuge. Pour the liquidy wish to separate into a test tube. Do not pour all the way to the top. Leave the test tube half empty. You need an even number of test tubes. If you do not have an even number of samples, fill a test tube with water to the same height as the sample. It is very important that each test tube has another test tube placed directly opposite it in order to keep the centrifuge balanced. Our centrifuge has six positions. All positions are numbered. When placing a test tube into the centrifuge, make note of the position number. Make sure every tube in the machine has a corresponding tube directly opposite to it for balance. Close the lid and turn the dial to five minutes. Do not open the lid until the centrifuge has come to a complete stop. Remove samples from the centrifuge.