The Collaborative International Dictionary of English v.0.48:

South \South\, v. i. [imp. & p. p. Southed; p. pr. & vb. n.
   Southing.]
   1. To turn or move toward the south; to veer toward the
      south.
      [1913 Webster]

   2. (Astron.) To come to the meridian; to cross the north and
      south line; -- said chiefly of the moon; as, the moon
      souths at nine.
      [1913 Webster]