About three billion years ago or afterwards, the earth had a solid crust, frequently punctured by eruptions of molten rocks (volcanoes) and at places filled with hot boiling sea water. the sea water contained dissolved amino, methane, some minerals and salts. The primitive atmosphere of earth was devoid of free oxygen but rich in ammonia, methane and hydrogen, as found in the present atmosphere of Jupiter, Saturn, Uranus and Neptune. Other investigators have concluded that the principal constituents were carbon mono-oxide, carbon dioxide, N2 and hydrogen. The earth was also bombarded with high energy radiations from the sun.