May, 1705.] As soon as the campaign could be opened in Poland, he hastened to the army, which he had sent to the assistance of Augustus, on the frontiers of that kingdom; but, while he was thus supporting his ally, a Swedish fleet put to sea, to destroy Petersburg, and the fortress of Cronslot, as yet hardly finished. This fleet consisted of twenty-two ships of war, from fifty-four to sixty-four guns each, besides six frigates, two bomb-ketches, and two fire-ships. The troops that were sent on this expedition, made a descent on the little island of Kotin; but a Russian colonel, named Tolbogwin, who commanded a regiment there, ordered his soldiers to lie down flat on their bellies, while the Swedes were coming on shore, and then suddenly rising up, they threw in so brisk and well directed a fire, that the Swedes were put into confusion, and forced to retreat with the utmost precipitation to their ships, leaving behind them all their dead, and upwards of three hundred prisoners. (June 7.) However, their fleet still continued hovering about the coast, and threatened Petersburg. They made another descent, and were repulsed as before (June 25.): a body of land-forces were also advancing from Wiburn,[71] under the command of the Swedish general Meidel, and took their route by Shlusselburg: this was the most considerable attempt that Charles had yet made upon those territories, which Peter had either conquered or new formed. The Swedes were every where repulsed, and Petersburg remained in security. Peter, on the other hand, advanced towards Courland, with a design to penetrate as far as Riga. His plan was to make himself master of Livonia, while Charles XII. was busied in reducing the Poles entirely under the obedience of the new king he had given them. The czar was still at Wilnaw in Lithuania, and his general Sheremeto was approaching towards Mittau, the capital of Courland; but there he was met by general Levenhaupt, already famous by several victories, and a pitched battle was fought between the two armies at a place called Gemavershoff, or Gemavers. In all those actions where experience and discipline decide the day, the Swedes, though inferior in number, had the advantage. The Russians were totally defeated, (June 28.) and lost their artillery. Peter, notwithstanding the loss of three battles, viz. at Gemavers, at Jacobstadt, and at Narva, always retrieved his losses, and even converted them to his advantage. After the battle of Gemavers, he marched his army into Courland; came before Mittau, made himself master of the town, and afterwards laid siege to the citadel, which he took by capitulation.