"Cartesian" is named after the French mathematician and philosopher Rene Descartes, who lived from 1596 until 1650. Cartesian diver lab is used commonly in scientific experiments to illustrate principle of buoyancy. The objective of this Cartesian diver lab is to demonstrate Pascal's law and Archimedes' principles. Observation is the key to conduct this experimental study of the Cartesian diver. First a 2-liter bottle is filled with water to almost all the way to the top, then prepare the diver which is a test tube, fill the test tube about 50-60% with water, place the diver inside the bottle the diver should float near the water surface then secure the cap on the bottle. When the container is squeezed, the diver should sink to the bottom of the container. Release the bottle slowly, the diver should come up in reverse order. The Cartesian diver shows that air is compressible and water is incompressible. When the container is squeeze, the pressure from squeeze is distributed equal throughout the container and the volume of air in the diver decreases because of the increased pressure of the water surrounding the diver. Since the volume of air inside the diver decreased, and water filled up where the air use to be, the diver becomes denser and will begin to sink if enough pressure is applied. It begins to sink because it becomes denser so the upward force of the water is not great enough to keep the diver floating. When the container is not squeezed, the diver will float back ...