It is said that Archimedes discovered this principle by noticing that the body was lightly felt by the water of the same volume as his body soaked in the bathtub while bathing.
An object immersed in the liquid is lightened by the size of the buoyancy that works on the object. In other words, the magnitude of buoyancy is equal to the weight of the liquid that corresponds to the volume that the object has eliminated.
The point is, the weight of the cargo loaded on a vessel is equal to the weight of the liquid equivalent to the volume difference that the vessel has eliminated before and after the cargo load.
This principle is quite simple, but because it follows the law of nature, if the working environment of draft survey is done well, high accuracy can be obtained.
