The French attacked the Austrians, who were in order of battle in front of the city. They were outflanked, and driven back; the gates were cut down by axes, or blown to pieces by cannon, and the republicans stormed the place, taking 3000 prisoners, with a vast train of cannon and mortars. Clarke bore a conspicuous part as an active cavalry officer in all the subsequent operations of the French army, including the capture of Worms, with all its stores, and of Mentz, before which the army arrived on the 19th of October, after forced marches, performed amid torrents of rain; and the taking of Frankfort, which was ransomed from destruction and pillage on the payment of 500,000 florins.
On the 17th of March, after the rout of Bingen, he defended the passage of the Nahe, a German stream, which falls into the Rhine near the former place, and there he was of signal service to the retreating troops. He was present at the affair of Horcheim, which was afterwards annexed to France, and the capture of Landau, on the 17th of May. His distinguished bravery on these occasions obtained him the rank of General of Brigade, provisionally, the commission of which he received on the field of battle. He then received the command of three regiments of dragoons, which formed the advanced guard of the army of the Rhine.
Soon afterwards we find him exercising in this army the functions of Chef d'Etat-Major Général; but on the 12th of October, 1793, the Commissioners of the National Convention, in virtue of a most unjust decree of that tyrannical assembly, deprived him of his rank, as he happened to be at that time on their secret list of the suspected.
He received intelligence of this on the very evening before the Austrians stormed the French lines at Weissembourg, on the Lower Rhine, and he retired at once to Alsace, where he was confined on a species of parole; nor did he recover his military rank and position until after the downfall and death of the cruel and infamous Robespierre.
Under the protection of M. Carnot, who was then Minister of Public Safety, Clarke was placed at the head of a committee of military topography; and in this service he exhibited the greatest talent as a director and instructor, and spared no pains to fulfil the duties imposed upon him. The restless and suspicious Directory, in thus maintaining M. Carnot at the head of their affairs as minister, caused also the retention of Clarke, whose importance seemed to increase with that of his patron.
He was confirmed a General of Brigade in March, 1795; and on his appointment to the rank of General of Division, on the 17th of September, in the same year, our Irish exile could scarcely believe that fate had higher or more brilliant destinies in store for him; but now his talents as a diplomatist were about to be put in requisition. This was when the astonishing successes of Napoleon in Italy had alarmed the Directory, who dispatched Clarke to Vienna, entrusting to him the difficult mission of preparing the terms of the projected peace between Republican France and the Imperial Court; but, as he was adverse to the wishes of the Directory, and inimical to the task, his arrangements proved unfortunately disadvantageous to the French.
After this he visited the army of Italy, the General-in-Chief of which, being influenced by the Directory, placed him in a subordinate position, alike repugnant to his love of freedom and authority. As simple plenipotentiary, Clarke, after traversing Germany, showed himself at Vienna to be the political confidant of the powerful Directory, and, above all, of M. Carnot.
In the minute instructions given to General Clarke by the French Government we are enabled to trace him in his route, which lay through Piedmont, Milan, Medina, Bologna, and Venice; and by the Directory he—more than all their other diplomatic agents—was specially recommended to observe narrowly the secret purposes of the different great personages who held important positions at the court of Vienna.
"Your journey, M. Clarke," said the minister De la Croix, in a letter written on the 17th November, 1796, "will be sufficiently useful when you have no longer anything to know or to discover for the profit of the Republic or the cause of humanity." But it was generally believed—nay, it was openly asserted in Paris—that the mission of Clarke to Vienna was all a ruse, and was meant merely to conceal some artful plot woven by the Directory against Napoleon Bonaparte, before whose power and popularity they were beginning to tremble.
However, the Directory really wished a peace, and provisionally demanded an armistice; but Bonaparte, who had no desire to see a general peace in Europe, and, least of all, one formed by any person save himself, by his formidable interference and potent influence, caused the negotiations entirely to fail. We are enabled to perceive how the Directory, in their overtures for peace, above everything else counted on those territories which they could offer in exchange for Luxembourg and other provinces which they had annexed to France. This system of compensation admitted of alterations, which their envoy could vary at his pleasure, on perceiving the effect produced by each offer on the various members of the Austrian cabinet.