Carbonic acid gas, commonly known as choke-damp, is usually found in pits or the bottom of old wells. It is so called because it has often suffocated those who came into contact with it. In the pit of iniquity and in the old wells of worldliness this soul-choking damp still abounds. If you wish your spiritual life choked just go down into the darkness of prayerlessness, into the empty well of the world's pleasures. There is always as much poisonous gas there as will take your heavenly breath away