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The details of a phase-shift calculation of high-energy electron scattering by nuclei are given, together with some preliminary results. A new method for summing the Legendre series for the Coulomb scattering amplitude is described. The results indicate that the erst Born approximation does not give cross sections accurate enough for a reliable interpretation of the experiments. From a comparison of the few theoretical cross sections already obtained with the experiments in gold at 125 Mev, very tentative conclusions about the nuclear charge distribution are drawn. It is pointed out that an analysis of results at two or more energies will be a much more sensitive test of possible charge distributions.

The relativistic Coulomb interference problem is carefully examined in order to evaluate critically the equations used in analyzing experiments designed to test the forward ir-N dispersion relations. We show that with a suitable interpretation the nonrelativistic Bethe formula for the phase difference between the strong and electromagnetic contributions is valid. However, for high energy near forward scattering there are unknown contributions which can change this phase by 0(a) rad; this is to be compared with a magnitude of of ~2a rad. We further show that two previous relativistic calculations of 4> are incomplete. The effects of calculable radiative corrections such as soft photon emission or vacuum polarization are examined. For the former it is found that although their magnitude is relatively large, they can, in general, be neglected. The reason for this is that by folding an accurate measurement of the total cross section into the data analysis a compensation of errors is induced. No such compensation takes place for the case of vacuum polarization, and its contribution could be important. Finally, we investigate the effects of small admixtures to the strong interactions which are not of the form e^^K We find that they are unlikely to be of significance here provided they can be assumed to be < 20% of the complete amplitude.