The Turkish artillery attack of May 5, 1916, in the Erzingan sector was duplicated on May 7, 1916, but this time the Russians used their guns, and apparently with telling effect. For so devastating was the Russian fire directed toward the newly established Turkish trenches that the Turks had to evacuate their entire first line and retire to their second line of defensive works. Throughout the entire day on May 8, 1916, the Turks doggedly attacked the Russian positions. Losses on both sides were heavy, especially so on the Turkish side, which hurled attack after attack against the Russian positions, not desisting until nightfall. Though no positive gain was made thereby, the Russians at least were prevented from further advances. The same day, May 8, 1916, yielded another success for the Russians in the southern sector, south of Mush. There, between that town and Bitlis, stretches one of the numerous mountain ranges, with which this region abounds. On it the Turks held naturally strong positions which had been still more strengthened by means of artificial defense works. A concentrated Russian attack, prepared and supported by artillery fire, drove the Turks not only from these positions, but out of the mountain range. On May 9, 1916, engagements took place along the entire front. In the center fighting occurred near Mount Koph, in the Chorok basin southeast of Baiburt, and the Turks made some 300 prisoners. Farther south a Turkish attack near Mama Khatun was stopped by Russian fire. In the south another Turkish attack in the neighborhood of Kirvaz, about twenty-five miles northwest of Mush, forced back a Russian detachment after capturing some fifty men. All this time the Russians were industriously building fortifications along the Black Sea coast both east and west of Trebizond. During the night of May 9, 1916, the Turks made a successful surprise attack against a Russian camp near Baschkjoej, about thirty-five miles southeast of Mama Khatun. There a Russian detachment consisting of about 500 men, of which one-half was cavalry and one-half infantry, found themselves suddenly surrounded by the bayonets of a superior Turkish force. All, except a small number who managed to escape, were cut to pieces.