[en] Townsend and Huxley's technique has been used in measurements of the ratio of lateral diffusion coefficient to mobility D/μ in hydrogen and nitrogen at ambient temperature for the ranges of reduced electric field E/N of 0.15 < E/N < 127.09 Td and 0.61 < - E/N < - 233.2 Td respectively. The present results have been compared with those obtained by other authors. (author)