Constaníinople, May ÍS. - There was a sudden and unexpected change in the political situation shortly before noon Tuesday. Russia qüietly showed her har.d and thereby forced Germany and Turkey out of the game to all intents and purposes. Monday night and early Tuesday morning Tur'tey, snppoited by Gcrmany, was practicaïiy defying Russia, Pranee, Austria, Great Britain and Italy, insisting upon the annexation of Thessaly in addition to a huge war indemnity, and seemingly was determined to march upon Athens. The ministers reeeived official advices from Sofia Tuesday announcing that orders had been issued for the partial mobilization of the Bulgarian army possibly, at the instigation of Russia. There was a hurried consultation of the ministers. The war party was for further defiance, but in the end paoific counsels seemed to have prevailed, for at 11:30 a. m., orders were telegraphed to Edhem Pasha. the Turkish oommander-in-chief in Thessaly, to cease hostilities. The peace negotiations will now be undertaken in real earnest, and the Greeks will rnost likely be spared any further humiliation.