In 1769 he selected eleven-year-old Ann Kingston (later renamed Sabrina Sidney) from an orphanage in Shrewsbury. At the Foundling Hospital in Coram Fields he selected the twelve-year-old Dorcas Car (later renamed Lucretia). (3) Anna described Sabrina as "a clear, auburn brunette, with dark eyes, glowing bloom and chestnut tresses", and Lucretia as her balanced opposite, "fair, with flaxen locks and light eyes". (4)

Day sent the two girls to Avignon to see which of them he could educate into becoming a suitable wife for himself. After eight months the trio returned to England. He decided that Lucretia was "either stupid or impossibly stubborn" and apprenticed her to a milliner on Ludgate Hill. Later she married a linen-draper. (5)

Day considered Sabrina as a possible wife. In 1770, aged 13, she went to live with him at Stowe House in Lichfield. She was described as a "sweet-voiced beauty, with long eyelashes and auburn ringlets". Despite his efforts, Sabrina did not develop as he wished and by the time she was 14 she had been sent to a girls' boarding school in Sutton Coldfield. (6) Anna Seward had been closely involved in this experiment and claimed that it made him doubt the truth of the ideas of Jean-Jacques Rousseau. "His trust in the power of education faltered". (7)

As a consequence of his relationship with Richard Lovell Edgeworth, Thomas Day joined the Lunar Society of Birmingham. The group took this name because they used to meet to dine and converse on the night of the full moon. Other members included Matthew Boulton, James Watt, Erasmus Darwin, Josiah Wedgwood, Joseph Priestley, James Brindley, William Small, John Whitehurst, John Robison, Joseph Black, William Withering, John Wilkinson, and Joseph Wright. This group of scientists, writers and industrialists discussed philosophy, engineering and chemistry. (8)

As Maureen McNeil has pointed out: "These innovating men of science and industry were drawn together by their interest in natural philosophy, technological and industrial development, and social change appropriate to these concerns. The society acquired its name because of the practice of meeting once a month on the afternoon of the Monday nearest the time of the full moon, but informal contacts among members were also important." (9)

Thomas Day was a strong opponent of slavery and in 1773, with his friend, John Bicknell, he wrote The Dying Negro. The poem was based on a reported incident. A black slave is said to have fallen in love with the white servant of his master, the captain of a slave ship. To marry her he has himself baptised, but when his master hears of this the slave is sent for transportation to America. Rather than go, he stabs himself with the words: "Thanks, righteous God! Revenge shall yet be mine." (10)

Day also condemned America's role in the slave-trade and argued in Fragment of a Letter on the Slavery of Negroes (1776): "You do not go to Africa to buy or steal your Negroes, perhaps because you are too lazy and luxurious: but you encourage an infamous, pitiless race of men to do it for you, and conscientiously receive the fruits of their crimes. You do not, merciful men, reduce your fellow-creatures to servitude... men of liberal minds like yours acknowledge all mankind to be their equals... Your worst actions, therefore, the greatest crimes which even your enemies can object to are only that you are the voluntary causes of all these mischief! You, you encourage the English pirate to violate the laws of faith and hospitality, and stimulate him to new excesses by purchasing the fruits of his rapine. Your avarice is the torch of treachery and civil war which desolates the shores of Africa, and shakes destruction on half the majestic species of man." (11)

Jean-Jacques Rousseau was one of those who rejected Day's views on the subject of slavery. He said, it was an "unjust reflection" upon the Americans, who "had not the less right to defend their liberties because they were obscure or unknown". Rousseau thought it was important to support the American rebellion despite the "existence of slavery in the Colony". He went onto attacking Day for writing "upon subjects that he did not understand". (12)

Thomas Day married Esther Milnes, an heiress from Chesterfield, the daughter of Richard Milnes, at Bath on 7th August 1778. "While not totally submerging her own personality, and doubtless distressed at having to surrender her poetry, harpsichord, and friends to comply with her husband's demands, Esther proved a satisfactory soulmate, and their marriage was close and loving.... The Days were to have no children, though Thomas Lowndes, Esther's nephew, became for all practical purposes their adopted heir." (13)

Other members of the Lunar Society, including Josiah Wedgwood, Matthew Boulton, Joseph Priestley and Erasmus Darwin also became involved in the campaign against the slave-trade. (14) The anti-slavery movement continued to use the The Dying Negro openly as propaganda for their cause. (15) In 1782 he published Reflections on the Present State of England and the Independence of America where he pointed out that the American treatment of their slaves formed a hypocritical contrast with their claims of the equality of man. (16)

Day also became involved in the campaign for parliamentary reform. Day purchased an estate at Anningsley, where he and Esther took up full-time residence in 1783. "They ran it primarily as a philanthropic concern, with the bodily and spiritual welfare of its workers and their families of paramount importance. In desolate surroundings, they laboured to create a new Jerusalem. A pioneer in every sense, Day was not only conscious of the hazards of air pollution, and a campaigner for land reclamation, but an early exponent of afforestation". (17)

Thomas Day refused to make a profit from the labour of those poorer than him, and boasted a £300 annual loss on his farm and allowed his workers an extra shilling for clothes and meat during the winter months. He refused to become involved in the parish relief system, which he believed to be under-funded, and so paid his farm labourers during winter, even though there was no work to do. This made him very unpopular with local landowners as their labourers demanded that they should be treated in the same way as those employed by Day. (18)

During this period he wrote a series of books for children. The most successful of these was The History of Sandford and Merton, a book that was published in three volumes (1783, 1786, and 1789). "The story tells how rebellious Tommy Merton, the spoilt son of a wealthy plantation owner from Jamaica, and his friend Harry Sandford, the poor but worthy son of a local farmer, are patiently educated by the Revd Mr Barlow - and how Master Tommy is brought, by precept and self-discovery, to see the error of his ways. A host of interpolated stories, providing introductions to ancient history, astronomy, biology, science, exploration, and geography, enable facts and figures to be absorbed relatively painlessly but the main narrative easily holds the attention."

Peter Rowland goes on to argue: " Rousseau's deductive techniques are deployed to good effect. What comes through is the basic Christian (and early socialist) message that the members of society should be kind not only to each other but also to the poor and the sick, to those of a different race, and to animals, birds, and insects. They should labour to the best of their ability and contribute to a common pool of goods and happiness. But for the idle rich, particularly those who wear fine clothes, play cards, and treat lesser mortals with contempt, the author has no mercy. The book, however sententious, would play a crucial role in moulding the ethos of nineteenth-century England." (19)

Thomas Day was thrown from his horse on 28th September 1789 and died almost instantly. He was buried at St Mary's Church, Wargrave, Berkshire, on 6th October 1789.

Child Labour Simulation (Teacher Notes)

Road Transport and the Industrial Revolution (Answer Commentary)

Richard Arkwright and the Factory System (Answer Commentary)

Robert Owen and New Lanark (Answer Commentary)

James Watt and Steam Power (Answer Commentary)

The Domestic System (Answer Commentary)

The Luddites: 1775-1825 (Answer Commentary)

The Plight of the Handloom Weavers (Answer Commentary)

(1) Peter Rowland, Thomas Day : Oxford Dictionary of National Biography (2004-2014)

(2) Claudia T. Kairoff, Anna Seward and the End of the Eighteenth Century (2011) page 214

(3) Anna Seward, Memoirs of the Life of Dr. Darwin (1804) page 35

(4) Wendy Moore, How to Create the Perfect Wife (2013) page 74

(5) Anna Seward, Memoirs of the Life of Dr. Darwin (1804) page 36

(6) Jenny Uglow, The Lunar Men (2002) page 187

(7) Kate Iles, Sabrina Sidney : Oxford Dictionary of National Biography (2004-2014)

(8) Anna Seward, Memoirs of the Life of Dr. Darwin (1804) page 41

(9) Joel Mokyr, The Enlightened Economy: Britain and the Industrial Revolution (2009) page 49

(10) Maureen McNeil, Erasmus Darwin : Oxford Dictionary of National Biography (2004-2014)

(11) Thomas Day and John Bicknell, The Dying Negro (1773)

(12) Thomas Day, Fragment of a Letter on the Slavery of Negroes (1776)

(13) Brian Dolan, Josiah Wedgwood: Entrepreneur to the Enlightenment (2004) pages 303-304

(14) Peter Rowland, Thomas Day : Oxford Dictionary of National Biography (2004-2014)

(15) Jenny Uglow, The Lunar Men (2002) page 414

(16) Jack Gratus, The Great White Lie (1973) page 112

(17) Jeremy Black, A Brief History of Slavery (2011) pages 147-148

(18) Peter Rowland, Thomas Day : Oxford Dictionary of National Biography (2004-2014)

(19) Peter Rowland, The Life and Times of Thomas Day (1996) page 249

(20) Peter Rowland, Thomas Day : Oxford Dictionary of National Biography (2004-2014)