  The first determination of the perihelion advance of Mercury's orbit was
obtained by Leverrier from the analysis of the transit contacts of the planet
on the solar disk. He obtained for the advance the value \delta \pi ' =
38".3/century, considering that the value \delta e', namely the correction of
the variation of the planet's orbit eccentricity, is negligible. In this paper
\delta \pi ' and \delta e' are calculated by the least squares method, on the
basis of the meridian observations used by Leverrier. Thus, we obtain for
advance the value \delta \pi ' = 42".8/century, which is close to the one given
in the theory of general relativity. The same, we obtained the value \delta e'
= -0".044/year, which is lower in absolute value than Leverrier's estimation
\delta e' = -0".0806/year.
