Bathometer is a device that helps us to measure the depth of water bodies like oceans, lakes or rivers. It works by using sound waves that bounce off the bottom of the water body and then come back to the device. The device then calculates the time it took for the sound waves to come back and uses this information to determine the depth of the water. It's kind of like when you shout into a big cave, and you can hear your echo coming back to you. The bathometer is used by scientists and engineers to gather information about the ocean floor, such as its shape, depth, and the types of rocks and sediment that make it up. This information helps us to better understand the ocean and its ecosystem, and it can also be useful for things like building underwater pipelines or constructing offshore platforms.