A measurement of Deltasigmasub ital L(ital np), the difference between neutron-proton total cross sections for pure longitudinal spin states, is described. Data were taken at LAMPF for five neutron ...beam kinetic energies: 484, 568, 634, 720, and 788 MeV. The statistical errors are in the range of 0.64--1.35 mb. Various sources of systematic effects were investigated and are described. Overall systematic errors are estimated to be on the order of 0.5 mb and include an estimate for the uncertainty in the neutron beam polarization. The Deltasigmasub ital L results are consistent with previous results from PSI and Saclay. These data, when combined with other results and fitted to a Breit-Wigner curve, are consistent with an elastic ital I=0 resonance with mass 2214plus minus15 (stat) plus minus6 (syst) MeV and width 75plus minus21plus minus12 MeV. Because of a lack of Deltasigmasub ital T(ital np) data between 500 and 800 MeV, it is not possible to differentiate between a singlet or coupled-triplet partial wave being responsible.
