♦Campaign of 1686.♦ His chances of success were excellent. The Emperor promised his aid on the side of Hungary; and a great army of Muscovites was to push forward to the Black Sea. After arranging his plans with the Imperial generals, John assembled his forces at the Dniester, but he found all alike, officers and men, indisposed to a campaign beyond the borders of Poland. But he could not now draw back. He advanced through the deserts of Moldavia to the Pruth, passing on his way the fatal spot where Zolkiewski met with a hero’s death. Descending the river he entered Yassy, the capital, on the 15th of August, and found that the hospodar had fled with his troops, but had left provisions for the invading force, thinking by this means to secure his immunity from punishment, whatever might be the result of the campaign. After two days of rest John pushed on towards the Black Sea. But the heat, the scarcity of water, and the terrible solitude[125] broke the spirit of his army, and suddenly the Tartars appeared in his front. News also arrived that the Turks were within a march of him, and there was no sign either of Muscovite or Austrian succours. Leopold had again deceived him, and had profited by John’s demonstration to capture the city of Buda. There was nothing left but to retreat, and this the king successfully accomplished, through a most difficult country, in the face of the enemy. The Tartars poisoned the rivers and springs, and set fire to the vegetation, while searching clouds of dust and ashes distressed the retiring Poles. At length they reached the frontiers of Poland; and the only person who had reaped any benefit from their sufferings was the Emperor Leopold. ♦Deposition of the Sultan.♦ In the following year a revolution at Constantinople, provoked by continued disasters, deprived Mahomet IV. of his throne; and had there been a complete accord between the members of the Christian league, the Ottoman empire might have tottered to its fall. No soldier of the Church had laboured more steadily towards this end than John Sobieski; and if it was not realised, the fault lay not with him but with his more powerful allies. ♦Polish anarchy.♦ As his reign drew near its close, the internal disorders of his kingdom increased. The Emperor never ceased to intrigue with the Lithuanian grandees against his faithful ally, and the French party opposed him for this fidelity to the league. The lesser nobility was devoted to him; but the Senate was now the hotbed of faction. All the grandees wished for the end of his reign, the French party because they disliked his policy, and the Lithuanians because they hated his person. Besides this, every ambitious senator looked to an interregnum as a means of realising his dreams of power.