A minimum observed in the high-angle scattering yield for 415 kev protons incident on single-crystal quartz along directions close to that of the [0001] axis has an angular width indicating channelling of the protons by atomic rows. Comparison between the spectra of protons scattered from the quartz and from vitreous silica shows that the channelled protons could travel a mean distance of approximately 1.75 micron before being scattered into the random mode.