A hydraulic ram is a clever device invented over 200 years ago that can pump water uphill with no other external source of power except for the water flowing into it and there is a way to take advantage of this normally inauspicious effect for a beneficial use.
source/image: Practical Engineering
The ram pump is an ingenious way to take advantage of the properties of fluids. We all need water for a variety of reasons, so being able to move it where we need it without any fancy equipment or external sources of power is a pretty nice tool to have in your toolbox. Watch the video from Practical Engineering for more info:
It takes in water at one “hydraulic head” (pressure) and flow rate, and outputs water at a higher hydraulic head and lower flow rate.
The device uses the water hammer effect to develop pressure that allows a portion of the input water that powers the pump to be lifted to a point higher than where the water originally started.