Writing as Major Harold Ridley, he published in 1944 a short paper in the British Journal of Ophthalmology on spitting snakes and an account on the composition and action of snake venom in general. From his own experiences in the Gold Coast, Ridley described snake venom ophthalmia in a 30-year-old labourer named Gogi Kumasi who was cutting grass when a Black-necked cobra raised its head from the grass and forcibly spat venom toward the man's right eye from a distance of four or five feet.