A ferromagnetic material having a rectangular hysteresis loop can be magnetized much easier if a magnetic field is applied transverse to the direction of remanence at the same time the remagnetizing pulse is applied. This effect, which has been observed in cores of ferrite, rolled Permalloy and vacuum‐deposited alloys, is shown to be compatible with the existing theories of domain wall motion. It forms the basis of an improved method of writing into magnetic memory cores in a digital computer.