The best plan for the French Government would have been to send to the Rhine all the seasoned troops left available by Napoleon III.'s ill-starred Mexican enterprise, so as to help the hard-pressed South German forces, offering also the armed mediation of France to the combatants. In that case Prussia must have drawn back, and Napoleon III. could have dictated his own terms to Central Europe. But his earlier leanings towards Prussia and Italy, the advice of Prince Napoleon ("Plon-Plon") and Lavalette, and the wheedlings of the Prussian ambassador as to compensations which France might gain as a set-off to Prussia's aggrandisement, told on the French Emperor's nature, always somewhat sluggish and then prostrated by severe internal pain; with the result that he sent his proposals for a settlement of the points in dispute, but took no steps towards enforcing them. A fortnight thus slipped away, during which the Prussians reaped the full fruits of their triumph at Königgrätz; and it was not until July 29, three days after the Preliminaries of Peace were signed, that the French Foreign Minister, Drouyn de Lhuys, worried his master, then prostrate with pain at Vichy, into sanctioning the following demands from victorious Prussia: the cession to France of the Rhenish Palatinate (belonging to Bavaria), the south-western part of Hesse Darmstadt, and that part of Prussia's Rhine-Province lying in the valley of the Saar which she had acquired after Waterloo. This would have brought within the French frontier the great fortress of Mainz (Mayence); but the great mass of these gains, it will be observed, would have been at the expense of South German States, whose cause France proclaimed her earnest desire to uphold against the encroaching power of Prussia. Bismarck took care to have an official copy of these demands in writing, the use of which will shortly appear; and having procured this precious document, he defied the French envoy, telling him that King William, rather than agree to such a surrender of German land, would make peace with Austria and the German States on any terms, and invade France at the head of the forces of a united Germany. This reply caused another change of front at Napoleon's Court. The demands were disavowed and the Foreign Minister, Drouyn de Lhuys, resigned[5]. [5] Sybel, _op. cit._ vol. v. pp. 365-374. Débidour, _op. cit._ vol. ii. pp. 315-318. See too volume viii. of Ollivier's work, _L'Empire libéral_, published in 1904; and M. de la Gorce's work, _Histoire du second Empire_, vol. vi. (Paris 1903).