In 1864 he went as Hessian envoy to Vienna, retiring in 1872 when the post was abolished.
Many reforms in ecclesiastical, educational, financial and administrative matters were introduced, and in general the grand-duchy may be said to have passed largely under the influence of Prussia, which, by an arrangement made in 1896, controls the Hessian railway system.
The Hessian in that case is a factor of f, and Q is the third power of u2,...
This can be verified by equating to zero the five coefficients of the Hessian (ab) 2 axb2.
The quartic will have two pairs of equal roots, that is, will be a perfect square, if it and its Hessian merely differ by a numerical factor.