Cross sections for production of positive and negative charge for 10-300-keV/u ~e ' + ions on He, Ne, Ar, Kr, Hz, N2, CO, 02, CH4, N20, and C02 were measured by the transverse-field method. Single-and double-electron-capture cross sections at 5-150 keV/u for the same targets were measured by the method of deflection of different charge-state components of the beam after passing through a known length of target gas. A secondary-emission detector was used to detect the neutral component of the beam. A small least-squares adjustment of the cross sections was made to satisfy the equation u+ =a-+u2, +2uZ0 which follows from conservation of charge.