Botanologia: The English Herbal: Or, History of Plants vol. 1, p. 492 (1710)
William Salmon

V. The second, or Hearts-Ease with double Flowers. This is a very pleasing Plant, and bears Flowers with more Leaves than the former, making it seen to be twice double, and that only in Autumn, for the first Flowers, which come in Summer, are single; this is of that sort which bears Purple Flowers, and it is to be noted, that the Seed of this Kind will not all bring double Flowers, but only some of them, where the Ground is fit, and the Plant thrives and takes a liking to it; so that if you have once had of this Double Kind, you shall seldom miss to have double Flowers again every Year of its own growing or sowing.