Today, life, our life, is just a link in a chain of innumerable living beings that have succeeded one another on Earth over nearly four billion years. And even today,new volcanoes continue to sculpt our landscapes. They offer a glimpse of what our Earth was like at its birth-molten rock surging from the depths, solidifying, cracking,blistering or spreading in a thin crust, before falling dormant for a time. These wreaths of smoke curling from the bowels of the Earth bare witness to the Earth’s original atmosphere. An atmosphere devoid of oxygen. A dense atmosphere, thick with water vapor, full of carbon dioxide. A furnace. But the Earth had an exceptional future, offered to it by water. At the right distance from the sun-not too far, not too near-the Earth was able to conserve water in liquid form. Water vapor condensed and fell in torrential downpours on Earth, and rivers appeared. The rivers shaped the surface of the Earth, cutting their channels, furrowing out valleys. They ran toward the lowest places on the globe to form the oceans. They tore minerals from the rocks and gradually the freshwater of the oceans became heavy with salt. Water is a vital liquid. It irrigated these sterile expanses. The paths it traced are like the veins of a body, the branches of a tree, the vessels of the sap that it brought to the Earth. Nearly four billion years later; somewhere on Earth can still be found these works of art, left by the volcanoes’ ash, mixed with water from Iceland’s glaciers. There they are-matter and water, water and matter, soft and hard combined, the crucial alliance shared by every life-form on our planet. Minerals and metals are even older than the Earth.