Born at
Pembroke in Wales, on 4 December 1795, he was the eldest child of John Walker, a naval officer, who died at
Twickenham in 1811 from the effects of wounds received in action. The boy was named after his godfather, Admiral
Sir Sidney Smith, under whom his father had served. His mother's maiden name was Falconer. William Sidney, always called Sidney, spent some years at a school at
Doncaster, kept by his mother's brother, and with a private tutor at
Forest Hill; he then entered
Eton College in 1811. At Eton he learnt the whole of
Homer by heart, and wrote Greek verse with facility. There, too, he began lifelong friendships with
Winthrop Mackworth Praed and
John Moultrie. Walker, small, uncouth and absent-minded, was bullied at school. He was entered as a
sizar at
Trinity College, Cambridge, on 16 February 1814, but did not come into residence until the following year. He won the Craven scholarship in 1817, and the Porson prize for Greek verse in 1818, and he was admitted scholar of Trinity on 3 April of the latter year. Although his weak mathematics rendered his passing the examination for the degree of B.A. in 1819 difficult, he was elected for his classical attainments to a fellowship at his college in 1820. He maintained close relations with Praed and Moultrie, and formed a friendship with
Derwent Coleridge. In 1824 he was an unsuccessful candidate for the Greek professorship at Cambridge. He made no other effort to engage in educational work. While a fellow of Trinity he lived in seclusion in his college rooms, reading
desultorily. As an undergraduate Walker had religious doubts, and had applied for guidance to
William Wilberforce. During 1818–19 Wilberforce wrote him letters in which he endeavoured to confirm his beliefs. The influence of
Charles Simeon helped him for a time; but he deemed himself disqualified by his sceptical views regarding
eternal punishment from taking
holy orders. As a consequence he resigned his fellowship in 1829. Without income, he fell into debt. His friend Praed came to his assistance in 1830, and, after paying his debts, settled on him an income for life of £52 a year; Trinity College added £20. Walker moved to London in 1831, lodging at first in
Bloomsbury, and then in the neighbourhood of St. James's Street. He lived entirely alone, and suffered from mental illness. He neglected himself, and social life. He died of
the stone at his lodging, a single room on the top floor of 41 St. James's Place, on 15 October 1846. He was buried in
Kensal Green Cemetery. On the tomb were engraved some lines from his friend Moultrie's poem
The Dream of Life. ==Works==