Oscar Edward Meinzer was a very smart and important person who studied and worked with water. He wanted to find out more about how water moves in the ground under the soil.
So, imagine that there is a big sponge under the ground. This sponge can soak up water when it rains and release it slowly over time. Oscar wanted to understand how this sponge worked and how it can be used to get fresh water for people to drink or use for farming.
To study this, he created special wells and tools that could help him measure how much water was in the sponge and how quickly it was moving. These tools were like special rulers and measuring cups, but for water under the ground!
Thanks to Oscar's hard work and discoveries, we now know a lot more about how water moves in the ground, and we can use this knowledge to help people have access to clean and fresh water.