  In the present work we calculate the group structure of the Schlesinger
transformations for isomonodromic deformations of order two Fuchsian
differential equations. We perform these transformations as the isomorphisms
between the moduli spaces of the logarithmic sl(2)- connections with fixed
eigenvalues of residues at singular points. We give the geometrical
interpretation of the Schlesinger transformations and perform the calculations
using the techniques of the modifications of bundles with connections. In order
to illustrate this result we present classical examples of symmetries of the
hypergeometric equation, the Heun equation and the sixth Painlev\'e equation.
