  In 1981 F. Knight published an article with a partial solution to a problem
proposed by Ito-McKean see [Ito,[p.217]]. In this paper Knight, see [Knight],
characterized the Levy measures of gap diffusions also known as
quasi-diffusions. The proof is very elegant but it uses quite a lot functional
analysis, more specifically spectral Krein Theory. We present a new proof of
Knight's Theorem, defined at the beginning of the Introduction as well as the
new proof of the same theorem referred as Theorem 2.6 in Section 2.
