# Dictionary of National Biography, 1885-1900/Tredgold, Thomas

​TREDGOLD, THOMAS (1788–1829), engineer, was born at Brandon, near the city of Durham, on 22 Aug. 1788. After receiving a slight elementary education at the village school he was apprenticed at the age of fourteen to a cabinet-maker at Durham. He remained with him six years, devoting his leisure to the study of mathematics and architecture, and taking advantage of the holidays granted on race days to acquire a knowledge of perspective. In 1808, after his apprenticeship had expired, he proceeded to Scotland, where he laboured for five years as a joiner and journeyman carpenter. To gratify his desire for knowledge he denied himself sleep and relaxation, and thereby permanently impaired his health. On leaving Scotland he went to London, where he entered the office of his relative, William Atkinson, architect to the ordnance, with whom he lived for six years, and whom he served for a still longer period. At this time ‘his studies combined all the subjects connected with architecture and engineering; and in order that he might be able to read the best scientific works on the latter subject, he taught himself the French language. He also paid great attention to chemistry, mineralogy, and geology, and perfected his knowledge of the higher branches of mathematics.’
In 1820 he published ‘Elementary Principles of Carpentry’ (London, 4to), in which he considered the problems connected with the resistance of timber in relation to making floors, roofs, bridges, and other structures. He also appended an essay on the nature and properties of timber. With the exception of Barlow's ‘Essay on the Strength of Timber and other Materials’ in 1817 [see Barlow, Peter], Tredgold's work was the first serious attempt in England to determine practically and scientifically the data of resistance. Before his time engineers relied chiefly on the formulæ and results attained by Buffon and by Peter van Musschenbroek in his ‘Physicæ Experimentales ​et Geometricæ’ (Leyden, 1729, 4to). Some of Tredgold's results were taken from Dumont's ‘Parallèle’ (Paris, 1767, fol.). Several editions of Tredgold's work have been published, and it remains an authority on the subject. The latest edition, by Edward Wyndham Tarn, appeared in 1886 (London, 4to). This work was followed in 1822 by ‘A Practical Essay on the Strength of Cast Iron and other Metals’ (London, 8vo; 5th edit., by Eaton Hodgkinson [q. v.], London, 1860–1, 8vo), which is mainly founded on the works of Thomas Young (1773–1829) [q. v.] Though they were long the standard text-books of English engineers, the scientific value of both these works is seriously impaired by Tredgold's lack of sufficient mathematical training, and more particularly by his ignorance of the theory of elasticity, which often leads him into error and always renders his reasoning obscure.
In 1823 the increase of business and the demands of literary labour led him to resign his position in Atkinson's office and to set up on his own account. In 1824 he published ‘Principles of Warming and Ventilating Public Buildings’ (London, 8vo), which reached a second edition in the same year (3rd edit., with appendix by Bramah, 1836). In 1825 appeared ‘A Practical Treatise on Railroads and Carriages’ (London, 8vo; 2nd edit. London, 1835), which was followed by a pamphlet addressed to William Huskisson [q. v.], president of the board of trade, and entitled ‘Remarks on Steam Navigation and its Protection, Regulation, and Encouragement’ (London, 1825, 8vo), which contained several suggestions for the prevention of accidents. His last important work, ‘The Steam Engine,’ appeared in 1827 (London, 8vo). A new edition, greatly enlarged, by Westley Stoker Barker Woolhouse, was published in 1838 (London, 4to); a third edition appeared in 1850–3 (London, 4to), and a French translation by F. N. Mellet in 1838 (Paris, 4to).
Tredgold died, worn out by study, on 28 Jan. 1829, and was buried in St. John's Wood chapel cemetery. He left in poor circumstances a widow, three daughters, and a son Thomas, who held the post of engineer in the office of stamps of the East India Company at Calcutta, where he died on 4 May 1853. The elder Tredgold's portrait and autograph are prefixed to the later editions of his ‘Steam Engine.’ Besides the works mentioned, Tredgold edited Smeaton's ‘Hydraulic Tracts’ (1826, 8vo; 2nd edit. 1837), added notes and articles to Robertson Buchanan's ‘Practical Essays on Millwork’ (ed. Rennie, London, 1841, 8vo), and revised Peter Nicholson's ‘New Practical Builder’ (London, 1861, 4to). He also contributed the articles on joinery and stone masonry to the supplement of the ‘Encyclopædia Britannica’ (ed. 1824), and contributed numerous technical articles to the ‘Philosophical Magazine’ and to Thomson's ‘Annals of Philosophy.’
[English Cyclopædia, Biography, vi. 153; London and Edinburgh Philosophical Mag. 1834, p. 394; Architectural Mag. 1834, p. 208; Todhunter's History of the Theory of Elasticity, i. 105–7, 454–6, 542, ii. 649; Artizan, 1859, xvii. 289; Encyclopædia Britannica, 8th edit. i. 876, xix. 402, xxi. 327; Dictionary of Architecture; Allibone's Dict. of Engl. Lit.]
E. I. C.