  The energy and nuclear mass dependences of the total hadronic cross section
in the energy range 0.5-2.6 GeV have been measured at Bonn using the SAPHIR
tagged photon beam. The measurement, performed on C, Al, Cu, Sn and Pb,
provides the first photoabsorption data in the region 1.2-1.7 GeV. The results
show a significant reduction of the photoabsorption strength on the bound
nucleon compared to the free nucleon case in the whole energy region. Above 1.2
GeV this reduction decreases with the nuclear density and can be interpreted as
a signature of a low energy onset of the shadowing effect.
