(d. Cambridge, England, 5 November 1732)
Bradley’s main scientific contributions were his studies on the movement of sap and on the sexual reproduction of plants. His experiments, particularly on trees, led him to consider sap as circulating in some way; from his work on tulips and hazel he drew analogies with animal reproduction, and emphasized the significance of pollination and the importance of insects in fertilization. He then went on to discuss the novel idea of cross-fertilization and the production of different strains. This work was published in his New Improvements of Planting and Gardening (1717) and A General Treatise on Husbandry and Gardening (1724).
Bradley was a prolific science writer, producing more than twenty botanical works, as well as writing on the plague at Marseilles in 1720, advocating cleanliness and a “wholesome diet” as prophylactics. His style was clear and readable, and his reputation immense; indeed, his publications did much to encourage a scientific approach to gardening and husbandry. Bradley claimed to have invented the kaleidoscope, which he used for preparing symmetrical designs for formal gardens, thus anticipating the claims of Sir David Brewster by some ninety years. He also strongly advocated the use of steam to power the irrigation of gardens and farmland.
On 1 December 1712 Bradley was elected a fellow of the Royal Society of London, and on 10 November 1724 was appointed to the chair of botany at Cambridge University. It is said he obtained the latter by claiming a verbal recommendation from the botanist William Sherard (1659–1728) and promising to provide a botanic garden at his own expense. He provided no garden and was unfamiliar with Latin and Greek, and, because of some supposed scandal, there was a petition to remove him. It proved of no avail, and he died in office. Sir Joseph Banks and other botanists named genera to commemorate him.
Bradley’s books include The Gentleman and Farmer’s Kalendar, Directing What Is Necessary to Be Done Every Month (London, 1718); New Improvements of Planting and Gardening, Both Philosophical and Practical; Explaining the Motion of the Sap and Generation of Plants (London, 1718); The Plague at Marseilles Consider’d: With Remarks Upon the Plague in General (London, 1721); Precautions Against Infection: Containing Many Observations Necessary to Be Considered, at This Time, on Account of the Dreadful Plague in France (London, 1722); A General Treatise on Husbandry and Gardening, 2 vols. (London, 1724); Philosophical Account of the Works of Nature (London, 1725); A Survey of Ancient Husbandry and Gardening (London, 1725); The Country Gentleman and Farmer’s Monthly Director (London, 1726); A Complete Body of Husbandry (London-Dublin, 1727); Dictionarium botanicum, 2 vols. (London, 1728); The Riches of a Hop-Garden Explain’d (London, 1729); A Course of Lectures Upon the Materia Medica (London, 1730); and Collected Writings on Succulent Plants, with an introduction by G. D. Rowley, a facsimile ed. (London, 1946).
His scientific papers include “Motion of Sap in Vegetables,” in Philosophical Transactions of the Royal Society, 29 (1716), 486–490; and “Some Microscopical Observations and Curious Remarks on the Vegetation and Exceeding Quick Propagation of Moldiness of the Substance of a Melon,” ibid., 490–492.
A work containing information on Bradley is Richard Pulteney, Historical and Biographical Sketches of the Progress of Botany in England, II (London, 1790), 129–133.
Colin A. Ronan