Whilst the greatest effort has been made to ensure the quality of this text, due to the historical nature of this content, in some rare cases there may be minor issues with legibility. Total Carbon, or Saturation Point for Car bon. The quantity Of carbon with which molten iron can combine (=combined graphitic carbon of the solidified iron) depends chiefly on the per centage Of silicon, sulphur and manganese which it contains. The former two elements lower the saturation point for carbon, while manganese raises it. Chemically pure iron can apparently only combine with about of carbon.