The general results of the analysis of more than four hundred glasses of the early occidental soda-lime type are reported. Samples came from Europe, North Africa, and Western Asia from the middle of the second millennium B.C. until the twelfth century A.D. Most specimens had a basically similar composition. Early glass was high in Mg content. Later glass was low in Mg content, followed by a return to high Mg content. There was essentially no correlation between concentrations of Mg and Ca. High Mg concentration is accompanied by a high K concentration. The difference in Mg concentration appears to be the result of inherently different raw materials. Several raw material possibilities are explored. Most of the glass samples had Mn and Sb compounds deliberately added during manufacture. These materials acted as opacifying agents. Sb oxides, however, have been found in clear glass. Pb was found in opaque red glasses containing Cu and Cu₂O or SnO. It is a possibility that oxidized or corroded bronze may have been added to glass melts to introduce Cu as a colorant. -- AATA