Hydraulic machines

For Christmas my cousins gave me a hydraulic machine set. Hydraulic means run by water. A few days after Christmas we used the kit and made hydraulic judo bots. It took a few hours to make them but we finally did it. After we made them we spent hours using them to fight the other robots. Next time we have 4th grade class I will bring two hydraulic robots with me and explain how they work (maybe only one). We used a website called instructables.com. This website tells you how to make a lot of hydraulic things and other experiments.