When of old the scared peasants beheld the irresistible advance of these strange ministers of destruction, they had no other resource than to fell their woods, abandon their dwellings, and surrender their "little all" to the pitiless sand and devouring sea. What could avail against such a scourge? Efforts were made to repel it. It is said that Charlemagne, during a brief residence in the Landes, on his return from his expedition against the Saracens, employed his veterans, and expended large sums of money in preserving the cities of the coast from imminent ruin; but whether the means employed were insufficient, or whether the imperial resources failed, and other urgent needs diverted the population and their leaders from this struggle against nature, the works were wholly abandoned. Of late years they have been resumed, and with greater success, by a skilful agriculturist, M. Desbiey, of Bordeaux, and an able engineer, M. Bremontier, who have called in nature herself to assist man in his war against nature. Their system consists of sowing in the driest sand the seeds of the sea-pine, mixed with those of the broom (_genista scoparia_), and the _psamma arenaria_. The spaces thus sown are then closely covered with branches to protect them from the action of the winds. These seeds germinate spontaneously. The brooms, which spring up rapidly, restrain the sand, while sheltering the young pines, and thenceforth the Dune ceases to move, because the wind can no longer unsettle its substance, and the grains are held together by the roots of the young plants. The work is always begun on the inland side, in order to protect the farmer and the peasant, and to withdraw the infant forest from the unwholesome influence of the ocean-winds. And, in order that the sown spaces shall not themselves be buried under the sands blown up from the shore, a palisade of wicker-work is raised at a suitable distance, which, reinforced by young plants of sandwort (_psamma arenaria_), check the moving sands for a sufficiently long time to favour the development of the seeds. Finally, the work is completed by the construction of a substantial wall, or rather an artificial cliff, which effectually prevents the further progress of the flood, or directs it seaward, to be arrested on its course by the barrier of the sand-hills. Unable to force a passage through these natural ramparts, they have excavated certain basins, more or less extensive, more or less deep, which have formed into inland seas, communicating with the Atlantic by one narrow issue.