In the frontier imposed upon her in 1815 France paid the penalty for Napoleon’s Hundred Days of glory. Toward the Rhine Landau was taken, and her territory was cut back to the Lauter. In Lorraine she lost the whole middle and lower portion of the Saar valley, including not only the new acquisitions about Saarbrücken but the town of Saarlouis, which had been French since its foundation. In theory the frontier of 1815 was to reëstablish the France of 1789. In fact it left France smaller than in 1789. And what was taken was given, not to the former rulers, still less to the inhabitants, but to Prussia. Whatever may be said against the claims of France in this region, Prussia had no rights there of any sort. Her nearest Rhenish possessions in 1789 had been a hundred and fifty miles away. She was established on the Rhine, not because the people wanted her, but because she wanted territory--Saxony, if possible, if not, something else--and because the Allies wanted somebody to watch France. So the reasons of the boundary line of 1815 are not far to seek. Landau and Saarlouis were fortresses of Vauban, defences of which it was thought prudent to deprive France, and this strategic argument has always been emphasized. We now know that the coal of the Saar was also a reason. This was openly stated by German historians before the war, and is supported by the correspondence of Heinrich Böcking, an agent of the German family of Stumm, still one of the great manufacturing firms of the region. Made commissioner of the mines in 1814, he followed the Prussian commissioners to Paris in the following year, and urged large annexations for Prussia at the expense of the Palatinate and France. In 1802 the French had opened a mining school at Geislautern, near Saarbrücken, and developed considerably the mines and industries of the region. Their careful surveys of the coal field were insistently demanded by the Prussians, and finally acquired in 1817. Some petitions from the inhabitants were received by the Prussians from Saarbrücken, but then there had been petitions in the opposite sense in 1797.