Digges, Leonard

(b. England, ca. 1520; d. England, 1559 [?])

mathematics.

Digges, a member of an ancient family in Kent, was the second son of James Digges of Barham. He was admitted to Lincoln’s Inn in 1537 and, if he received the usual education of young gentlemen of the time, may also have attended a university. His works are strongly indebted to contemporary Continental sources, and it is possible that he traveled abroad in 1542.

Digges was interested in elementary practical mathematics, especially surveying, navigation, and gunnery. His almanac and prognostication (1555) contains much material useful to sailors. In 1556 he published an elementary surveying manual, Tectonicon. Both of these works went through many editions in the sixteenth century. In 1571 his son Thomas completed and published his more advanced practical geometry Pantometria, the first book of which was an up-to-date surveying text. The material in these works is based largely on Peter Apian and Gemma Frisius, but in many cases Digges was the first to describe the instruments and techniques in English.

Digges was a keen experimentalist who gained a reputation, while still quite young, for skill in ballistics. Although his military treatise Stratioticos (1579) is largely the work of his son, it is based partly on his notes and the results of his gunnery experiments. The genesis of Stratioticos may be found in Digges’s association with Sir Thomas Wyatt and others in the preparation of a scheme for an organized militia for Protector Somerset in 1549.

Digges took part in Wyatt’s rebellion in 1554. He was attainted and condemned to death but was pardoned for life, probably through the intercession of his kinsman Lord Clinton (later earl of Lincoln), to whom the Prognostication was dedicated. He completed payments for the redemption of his property on 7 May 1558 and probably died shortly thereafter.

BIBLIOGRAPHY

I. Original Works. Digges’s writings are A Prognostication of Right Good Effect (London, 1555), enl. and retitled A Prognostication Everlasting (London, 1556; 11 eds. before 1600); A Boke Named Tectonicon (London, 1556; 8 eds. before 1600); A Geometrical Practise Named Pantometria (London, 1571, 1591), bk. 1, “Longimetria,” repr. by R. T. Gunther as First Book of Digges Pantometria, Old Ashmolean Reprints, 4 (Oxford, 1927); and An Arithmeticall Militare Treatise Named Stratioticos (London, 1579, 1590).

II. Secondary Literature. The Dictionary of National Biography article on Leonard Digges is wholly unreliable. Some biographical material can be found in D. M. Loades, Two Tudor Conspiracies (London, 1965); and E. G. R. Taylor, Mathematical Practitioners of Tudor and Stuart England (Cambridge, 1954). The works on surveying are discussed in E. R. Kiely, Surveying Instruments (New York, 1947); and A. W. Richeson, English Land Measuring to 1800 (Cambridge, Mass., 1967). The Stratioticos is discussed in Henry J. Webb, Elizabethan Military Science (Madison, Wis., 1965), with reference to Thomas Digges.

Joy B. Easton