Source : Webster's Revised Unabridged Dictionary (1913)

Deepness \Deep"ness\, n.
   1. The state or quality of being deep, profound, mysterious,
      secretive, etc.; depth; profundity; -- opposed to
      shallowness.

            Because they had no deepness of earth. --Matt. xiii.
                                                  5.

   2. Craft; insidiousness. [R.] --J. Gregory.

Source : WordNet®

deepness
     n 1: the quality of being physically deep; "the profundity of the
          mine was almost a mile" [syn: {profundity}, {profoundness}]
          [ant: {shallowness}]
     2: a low pitch that is loud and voluminous