Under the term of the 1815 Peace of Paris, France was obliged to pay for the construction of a line of fortresses to protect the German Confederation against any future aggression by France. Section C. "Defensive System of the Germanic Confederation" of the protocol drawn up at Paris on 3 November 1815, declared Mainz, Luxemburg, and Landau to be fortresses belonging to the Confederation of Germany, and stipulated that a fourth should be constructed on the Upper Rhine. In conformity with this act, a portion of the funds, which France was compelled to pay by way of indemnity for the cost of placing her on a peaceable footing, was thus appropriated: £200,000 were set aside for completing the works at Mainz; £800,000 were assigned to Prussia, to be applied upon its fortresses on the Lower Rhi