The same day Souvarow attacked Aerolo; but his luck had turned: the conqueror of Cassano, Trebia, and Novi had left his good-fortune behind in the plains of Italy. For twelve hours six hundred French opposed three thousand Russian grenadiers beneath the walls of the town, and so successfully that night fell without Souvarow being able to defeat them. Next day he marched the whole of his troops against this handful of brave men, but the sky clouded over and the wind. blew a bitter rain into the faces of the Russians; the French profited by this circumstance to beat a retreat, evacuating the valley of Ursern, crossing the Reuss, and taking up their position on the heights of the Furka and Grimsel. One portion of the Russian army’s design had been achieved, they were masters of the St. Gothard. It is true that as soon as they marched farther on, the French would retake it and cut off their retreat; but what did this matter to Souvarow? Did he not always march forward?
He marched on, then, without worrying about that which was behind him, reached Andermatt, cleared Trou d’Ury, and found Lecourbe guarding the defile of the Devil’s Bridge with fifteen hundred men. There the struggle began again; for three days fifteen hundred Frenchmen kept thirty thousand Russians at bay. Souvarow raged like a lion trapped in a snare, for he could not understand this change of fortune. At last, on the fourth day, he heard that General Korsakoff, who had preceded him and who was to rejoin him later, had been beaten by Molitor, and that Massena had recaptured Zurich and occupied the canton of Glaris. Souvarow now gave up the attempt to proceed up the valley of the Reuss, and wrote to Korsakoff and Jallachieh, “I hasten to retrieve your losses; stand firm as ramparts: you shall answer to me with your heads for every step in retreat that you take.” The aide-de-camp was also charged to communicate to the Russian and Austrian generals a verbal plan of battle. Generals Linsken and Jallachieh were to attack the French troops separately and then to join the forces in the valley of Glaris, into which Souvarow himself was to descend by the Klon-Thal, thus hemming Molitor in between two walls of iron.
Souvarow was so sure that this plan would be successful, that when he arrived on the borders of the lake of Klon-Thal, he sent a bearer with a flag of truce, summoning Molitor to surrender, seeing that he was surrounded on every side.
Molitor replied, to the field-marshal that his proposed meeting with his generals had failed, as he had beaten them one after the other, and driven them back into the Grisons, and that moreover, in retaliation, as Massena was advancing by Muotta, it was he, Souvarow, who was between two fires, and therefore he called upon him to lay down his arms instead.
On hearing this strange reply, Souvarow thought that he must be dreaming, but soon recovering himself and realising the danger of his position in the defiles, he threw himself on General Molitor, who received him at the point of the bayonet, and then closing up the pass with twelve hundred men, the French succeeded in holding fifteen to eighteen thousand Russians in check for eight hours. At length night came, and Molitor evacuated the Klon Thal, and retired towards the Linth, to defend the bridges of Noefels and Mollis.