In an earlier publication, an expression was derived for the sensitivity of a carbon-walled, carbon dioxide-filled ionisation chamber, for low-energy neutrons. This expression has been extended to allow its use for high-energy neutrons, and has been used to make detailed calculations for a particular ionisation chamber irradiated with either 15 MeV or 5.5 MeV neutrons. The results of these calculations are compared with experimental values and, within the stated limits, reasonable agreement is obtained.