Bathymeter

A bathymeter is a tool that helps people figure out how deep the water is in a certain area, like a lake or an ocean.

It works by sending out sound waves or sometimes light waves into the water. These waves travel through the water and bounce off the bottom. The bathymeter then measures how long it takes for the waves to bounce back, and uses that information to calculate the depth of the water.

Think of it like throwing a ball against a wall and counting how long it takes for the ball to come back to you. The time it takes for the ball to come back tells you how far away the wall is.

Scientists and engineers use bathymeters to make maps of the ocean floor and to figure out where it is safe to sail ships or install things like underwater pipelines. It's a really important tool for exploring and understanding the water world around us!