And he began to oppress the Israelites more than he had ever done before. They made bricks of clay mixed with straw, that hardened in the sun, and were as lasting as stone, but he forced them to find the straw wherever they could, and make as many bricks as before. This they did until no more straw could be found, and their Egyptian masters beat them cruelly because they failed to make the full number of bricks. Then they turned upon Moses and Aaron and said, that they had put a sword in the king's hand to slay them. Where could Moses turn except to the Lord who had sent him? The Lord heard him and made to him again the great promise, as he did at the burning bush, and Moses told the people, but they could not believe it, for they were crushed under their cruel burdens. And now the Lord sent Moses and Aaron again to Pharoah, to show by sign and miracle, that their message was from Him. They took the rod that Moses brought from Mount Horeb, and Moses told Aaron to cast it down before the king, and it became a serpent. Pharoah called his wise men and wizards, and they did the same, only Aaron's rod swallowed up their rods, and Pharoah would not listen to their words. [Illustration: The rod that troubled Egypt] But in the morning when Pharoah walked by the river the two men stood by him and said again: The Lord God of the Hebrews hath sent me unto thee saying: "Let my people go that they may serve me in the wilderness," and then Aaron struck the waters of the river Nile with his rod, and the waters turned to blood. In all the land, in every stream and pond there was blood, so that the fishes died and no one could drink the water. But because the wizards could turn water to blood also, Pharoah's heart was hardened toward Moses and Aaron. While the people were digging wells for water, Aaron stretched forth his rod over the river again, and frogs came up from it, and spread over all the land and filled the houses of the people. This also the magicians did, but so great was the plague that the king said: "I will let the people go." "When shall I entreat for thee and for thy people to destroy the frogs from thee and thy houses?" said Moses; and Pharoah told him to do so the next day. So on the next day Moses prayed to the Lord that the frogs might go out of the land, and the Lord answered his prayer; but when Pharoah saw that the frogs had been destroyed his heart grew hard, and he would not listen to Moses and Aaron. Then another plague was brought upon the Egyptians. The dust of the land was changed to lice that covered man and beast, and this was followed by swarms of flies that settled upon all the land except Goshen where the Israelites lived. Then Pharoah said: