Before revision: The mass fraction of element B at the liquids is given by wBl (represented as wl in this diagram) and the mass fraction of element B at the solidus is given by wBs (represented as ws in this diagram).
After revision: The mass fraction of element B at the liquidus is given by wBl (represented as wl in this diagram) and the mass fraction of element B at the solidus is given by wBs (represented as ws in this diagram).