A theory presented some years ago is reviewed in the light of recent evidence. Diamonds in meteorites appear to require high steady pressures at some time in their history, the Sun still is reported to contain less iron than the terrestrial planets and meteorites, and structures in iron meteorites still indicate that they did not originate from cores of asteroids. These as well as other evidence indicate that fairly large objects of approximately lunar size existed temporarily in the solar system and were destroyed. Fractionation of the metallic and silicate phases occurred leaving higher density materials to form the terrestrial planets. It was and is again suggested that gravitational instability in the solar nebula was the mechanism for the accumulation of the terrestrial planetary materials and for producing objects large enough to produce diamonds, and that adiabatic compression of gases produced the melting of the meteorites. It is suggested again that the Moon may be one of these primary objects accumulated in primitive gas spheres and that it is older than the Earth. The interaction of a solar magnetic field with ionized gases is accepted as the mechanism for the loss of angular momentum from the primitive Sun.