About the same period several Irish soldiers of fortune, driven from home by political troubles, appeared in the Turkish ranks, as well as not a few Poles, dispossessed by the "second partition" of their country, and longing for a chance of avenging the wrong. Several of these adventurers adopted the Mohammedan faith, and, gaining the entire confidence of their adopted countrymen, were enabled to inflict considerable injury upon the invading armies of Russia. But the greatest service rendered to the Crescent by a foreigner at that time (we might almost say the greatest which it ever received) was achieved in 1802 by the French envoy, Colonel (afterward General) Sebastiani. When a British squadron lay off Prinkipos Island, within easy reach of Constantinople, threatening it with instant bombardment, the undaunted ambassador, defying alike the hostile guns and the fury of the fanatical mob, calmly set himself to achieve the same task which General Todleben accomplished in the Crimea half a century later. Under his vigorous superintendence the city was impregnably fortified by the incessant labor of a single week, while a show of negotiation diverted the attention of the English admiral; and the hostile squadron, suddenly confronted by twelve hundred heavy guns, was forced to retire with considerable loss. The enlightened rule of Alexander I., whose zeal for the improvement of Russia quickened instead of keeping down his appreciation of foreign talent, filled the Russian camp with officers from Western Europe. Benningsen, the most formidable antagonist of Napoleon in 1807; Pfuhl, who constructed the fortified camp of Drissa in 1812; Barclay de Tolly, the Russian commander-in-chief in the early part of that memorable campaign; Wittgenstein, who bore the palm of valor during the invasion of France in 1814; the great strategist Jomini, who was Alexander's aide-de-camp; and Langeron, whose storming of Montmartre sealed the fate of Paris,--were all men of foreign blood. Even after the accession of the Russomaniac Nicholas in 1825, the "over-the-frontier men," as the natives emphatically call them, continued to hold the same prominent place. The Russian navy, indeed, which in the time of Catherine II. owed to Western Europe the only three competent seamen whom it possessed--Greig, Elphinstone and Dugdale--was by this time officered chiefly by native Russians, though still manned by Finns, Greeks and Livonians; but in the army Count Diebitsch himself, the hero of 1828-29, and his two principal subordinates, Generals Roth and Rüdiger, were of German descent. In the Crimean war the array of foreign names on either side was still more striking. Omar Pasha, perhaps the greatest general whom Turkey has ever possessed, was a Hungarian deserter from the Austrian army, his true name being Theodore Lattos. The defence of Silistria was the work of two English subalterns, Lieutenant Nasmyth and Captain Butler.