Water leveling is something you probably wouldn’t have seen since the early 20th century, and even then it was only used by surveyors.
Water Will Always Find It’s Own Level
The basic idea of a water level is that water will always find its own level.
If you have two jars of water and you connect them with a tube, the water level in both jars will be exactly the same, because water will flow between them until the surface of the water is at the same height in both jars.
This is why water leveling uses a tube containing water. You can set up a water level by simply holding up the two ends of the tube, and the water will find its own level.
Now, when you take a water level and you put it on a tripod, it will naturally level itself out. The water will find its own level as always, and since you’re holding the tube up with one of the ends higher than the other, it means that the water level will be parallel to the ground.
This is why water leveling can be used to measure the slope of a surface. If you’re using a water level on a surface that isn’t completely flat, the water level will become tilted, and you can see the angle of the slope by how much the water level is tilted.
Now, with a laser level, you have a laser beam that’s completely level with the ground. It’s that simple. The laser is firing out from the laser level at a right angle to the level of the device itself, and so the laser is level with the ground.
This means that a laser level will give you a level line, no matter what angle you’re using it at — just like a water level.
However, a water level will change its angle according to the slope it’s on, while a laser level always gives you a level line no matter what. This makes a laser level far more flexible for all kinds of different projects.