Construction

This simple machine shows the workings of the Stirling principle very well - it is built from glass parts.  

On this Japanese site you find detailed instructions how to build this machine and how it works. Again thanks to Koichi Hirata!

The first picture shows all the parts that we have used.

On the rightmost picture you can see (well, almost) how the marbles move the air between the hot and cold areas of the test tube, thereby expanding and contracting, which in turn moves the glass syringe on the left, which again moves the test tube up and down.

Click on the Pics to enlarge.