ON THE OCCASION OF THE 150TH ANNIVERSARY OF DARCY'S LAW

In the end of this year it will be a 150 years since Henry Philibert Gaspard Darcy (1803-1858) has performed first experiments which were a year after followed by publication of the famous monograph "Les fontaines publiques de la ville de Dijon" containing text Determination des lois d'ecoulement de l'eau a travers le sable. This work is fundamental because the basic law describing flow of liquid through the porous media is given therein. It describes the relation in which the double averaging of the flow velocity is introduced, and at the same time the theoretically correct energy approach to illustration of the groundwater flow is introduced. This law is without doubt the most important and the furthest reaching achievement of such exceptional scientist, who was both serious theoretician and also highly effective in practice. His scientific works are in a quite wide range - from water works to road building, and especially significant in hydrotechnics. Describing the wide scope and deep meaning of Darcy's law has remained an interesting subject even today. The "far sight" of Darcy's comprehension results from a simple fact - carefully performed and sharp-wittedly interpreted experiment. This gave the Darcy's law a theoretical clearness which allows its generalisation and extensions for various flow conditions in respect to the type of energy that controls the movement, type of liquid that flows and of the medium wherein the process takes place, also on the scale at which the process is studied. In this text, emphasis is primarily given to the results of original experiments and to the Darcy's original explanations of flow through the porous medium.