Swainsona formosa, or Sturt’s Desert Pea, is an Australian plant in the genus Swainsona, famous for its distinctive blood-red leaf-like flowers, each with a bulbous black centre, or ‘boss’.
The English explorer William Dampier made the first known recording of the species in 1699. The plant’s taxonomy has been changed on a number of occasions through the years. It was initially treated in the 18th century in the genus Clianthus as Clianthus dampieri, and later became more widely known as Clianthus formosus (formosus is Latin for ‘beautiful’).
However, it was later reclassified under the genus Swainsona as Swainsona formosa, the name by which it is officially known today, after the English botanist Isaac Swainson.
A Lancashire man by birth, Swainson moved to London where he served as assistant to a man named Dr Mercier. He later purchased from him the recipe of a patent medicine called ‘Velnos’s Vegetable Syrup’.
The origins of the concoction are unclear but, according to Marie E. McAllister writing in The Secret Malady, it was probably invented by Vergery de Velnos, either working with or succeeded by Dr Mercier.
Velnos’s Vegetable Syrup, alternatively referred to as Velno’s, Velnos’, de Velnos’, and De Velnos’s syrup, was among the best-known English non-mercury remedies for venereal diseases.
All were used to try and cure complaints commonly known at the time by euphemisms such as the ‘French disease’, ‘Cupid’s itch’, the ‘curse of Venus’, or in French, ‘la maladie de Cythére’.
Velnos’s Vegetable Syrup became so well-known that Swainson, who put himself forward as the “sole proprietor of the genuine medicine” in the 1780s and 1790s, reputedly made as much as £5,000 a year from its sales. He used some of the proceeds to achieve his dream of establishing his own botanical garden, at Heath Lane Lodge in Twickenham (right).
The above top illustration is from Paxton’s Flower Garden, by John Lindley and Sir Joseph Paxton, published in 1851.