Book of Knowledge (1826)
“ A Gentleman near Renfrew, has prosecuted an experiment on the effect of pulling the flowers or blossoms from the Potatoes, with great care and attention, in fields of two acres, each year, by taking alternate portions of equal area in the same field; Handling the blossoms from some of the divisions, and leaving others to ripen to seed; attending in the Autumn, when the Potatoes were taking up, and measuring the produce with great care, he uniformly found the quantity increase 10 or 15 percent. ”
