The following “RAM pump” 101 sketch accompanies a Water Preservation Society "Topical Tips" article in the Gulf Islands Driftwood on water catchment. Find It Here.
There are a number of online resources that illustrate how a RAM pump works, for example:
The SSI Water Preservation Society is a non-profit society that has been working to protect the water and watersheds of Salt Spring’s drinking-water lakes since 1982. The Society also owns and manages 272 forested acres on the slopes west of St. Mary Lake now protected by a conservation covenant.