  We suggest a particular procedure of derivation of the beta-stability line
and isotopic symmetry energy. The behavior of the symmetry energy coefficient
$b(A,N-Z)$ is analyzed. We redefine the surface tension coefficient and the
surface symmetry energy for an asymmetric nuclear Fermi-liquid drop with a
finite diffuse layer. Following Gibbs-Tolman concept, we introduce the
equimolar radius at which the surface tension is applied. The relation of the
nuclear macroscopic characteristics like surface and symmetry energies, Tolman
length, etc. to the bulk properties of nuclear matter is considered. The
surface-to-volume symmetry energy ratio for several Skyrme-force
parametrizations is obtained.
