This manufacture was carried on more extensively in Saintonge than in any other part of France. The salt was obtained by subjecting water drawn from the ocean to solar evaporation. The low marsh-lands which were very extensive about Brouage, on the south towards Marennes and on the north towards Rochefort, were eminently adapted to this purpose. The whole of this vast region was cut up into salt basins, generally in the form of parallelograms, excavated at different depths, the earth and rubbish scooped out and thrown on the sides, forming a platform or path leading from basin to basin, the whole presenting to the eye the appearance of a vast chess-board. The argillaceous earth at the bottom of the pans was made hard to prevent the escape of the water by percolation. This was done in the larger ones by leading horses over the surface, until, says an old chronicler, the basins "would hold water as if they were brass." The water was introduced from the sea, through sluices and sieves of pierced planks, passing over broad surfaces in shallow currents, furnishing an opportunity for evaporation from the moment it left the ocean until it found its way into the numerous salt-basins covering the whole expanse of the marshy plains. The water once in the basins, the process of evaporation was carried on by the sun and the wind, assisted by the workmen, who agitated the water to hasten the process. The first formation of salt was on the surface, having a white, creamy appearance, exhaling an agreeable perfume, resembling that of violets. This was the finest and most delicate salt, while that precipitated, or falling to the bottom of the basin, was of a darker hue. When the crystallization was completed, the salt was gathered up, drained, and piled in conical heaps on the platforms or paths along the sides of the basins. At the height of the season, which began in May and ended in September, when the whole marsh region was covered with countless white cones of salt, it presented an interesting picture, not unlike the tented camp of a vast army. The salt was carried from the marshes on pack-horses, equipped each with a white canvas bag, led by boys either to the quay, where large vessels were lying, or to small barques which could be brought at high tide, by natural or artificial inlets, into the very heart of the marsh-fields. When the period for removing the salt came, no time was to be lost, as a sudden fall of rain might destroy in an hour the products of a month. A small quantity only could be transported at a time, and consequently great numbers of animals were employed, which were made to hasten over the sinuous and angulated paths at their highest speed. On reaching the ships, the burden was taken by men stationed for the purpose, the boys mounted in haste, and galloped back for another.