Luirographe is a recording and measuring apparatus of water heights in underground cavities. It makes it possible to better know and understand the hydrological operation of the cavities. The study must be achieved over several years. The flood frequency and the height of water, the rising times, the speed of the wave in the cavity, the rise and fall times of the level of water can be studied. We can also study if there are outfalls and know in which order and at which speed the galleries are flooded. For example, in Luire cave, the arrival of walls of water in certain galleries, the outfalls and the flow of rivers have been studied.