“And the first sounded his trumpet: and there was hail and fire, mingled with blood, and they were cast upon the earth; and the third part of the earth was burnt up, and the third part of the trees was burnt up, and all green grass was burnt up.” Revelation 8:7
If we look at Revelation 12:3-4 we see that the dragon (Satan) drew with his tail the "third part" of the stars of heaven, and cast them to the ground, then stood before the pregnant woman (Israel) ready to devour her child (Christ). This speaks of the time when Herod the Great, the instrument of Rome, was seeking to kill the Lord Jesus as a young boy. If we are familiar with the symbology of Revelation we will know that stars represent those who are set in a position of authority. The dragon's tail drawing the third part of the stars corresponds to his efforts to bring the leaders of a great political power (fill in the blank) under demonic control. His purpose was to mobilize them to kill the man-child and thus thwart God’s purpose (Matt. 2). What political power was behind Herod? Rome. This passage gives us the key that “the third part” refers to the Roman earth.