Read the Douay-Rheims Latin Vulgate Bible everyday from Genesis to Apocalypse, the reading is currently at: Exodus 10:21-29
21 And the Lord said to Moses: Stretch out they hand towards heaven: and may there be darkness upon the land of Egypt, so thick that it may be felt. 22 And Moses stretch forth his hand towards heaven: and there came horrible darkness in all the land of Egypt for three days. 23 No man saw his brother, nor moved himself out of the place where he was: but wheresoever the children of Israel dwelt there was light. 24 And Pharao called Moses and Aaron, and said to them: Go sacrifice to the Lord: let your sheep only, and herds remain; let your children go with you. 25 Moses said: Thou shalt give us also sacrifices and burnt offerings, to the Lord our God.
21 "Darkness upon the land of Egypt, so thick that it may be felt"... By means of the gross exhalations, which were to cause and accompany the darkness.
26 All the flocks shall go with us: there shall not a hoof remain of them: for they are necessary for the service of the Lord our God: especially as we know not what must be offered, till we come to the very place. 27 And the Lord hardened Pharao's heart, and he would not let them go. 28 And Pharao said to Moses: Get thee from me, and beware thou see not my face any more: in what day soever thou shalt come in my sight, thou shalt die. 29 Moses answered: So shall it be as thou hast spoken, I will not see thy face any more.