With the invention of the tide-gate system in the mid-17th century, Acadians succeeded in drying and cultivating previously unproductive marshland. Consisting of a wooden caisson called a "dalle" in Acadia, and equipped with a one-way valve, the tide-gate was installed across a dike to allow water to drain off the land into the sea, while preventing tidal sea water from flooding back onto cultivated land. This water-control system which resulted from a collective effort reinforced the feeling of pride and identity among Acadians and provided significant economic benefits.