A cartesian diver


This is an experiment named after René Descartes (1596–1650). Descartes was a French scientist and philosopher. The Cartesian diver can be used to illustrate the behaviour of gases and liquids when compressed. In this experiment a Cartesian diver is constructed and some of the properties observed.



This practical is part of our Classic Chemistry Experiments collection.

If you teach primary science, click the headings below to find out how to use this resource:

Skill development

Children will develop their working scientifically skills by:

  • Asking their own questions about scientific phenomena.
  • Researching using a wide range of secondary sources of information.
  • Drawing conclusions and raising further questions that could be investigated, based on their data and observations.

Learning outcomes

Children will:

  • Make careful observations of what is happening in the demonstration.

Concepts supported

Children will learn:

  • How gases are more easily compressed than liquids.

Suggested activity use

This activity could be used to stimulate discussion around what the children are observing in the demonstration. It also could provide a stimulus for research into the phenomena they have seen or into the scientist that discovered it.

Practical considerations

This activity deals with some concepts around the density of gases and liquids which may be difficult for some children to understand.

Care will need to be taken when creating the diver otherwise the demonstration won’t work correctly.