Background
The son of Joseph Slack, a cloth merchant, and Grace Slack, he was born in London on 23 October 1818, and educated at North End, Hampstead.
The son of Joseph Slack, a cloth merchant, and Grace Slack, he was born in London on 23 October 1818, and educated at North End, Hampstead.
He gave up a business career for journalism in 1846, and worked on the North Devon Journal and other provincial papers. He was elected a Fellow of the Geological Society in 1849. In 1852, Slack became proprietor and editor of The Atlas, where Henry White was literary editors
He also wrote for the Weekly Times, under the signature "Little John".
Slack sold The Atlas back to Robert Bell at the end of the 1850s. Slack advocated liberal ideas: opposition to slavery, the abolition of the paper duties, and the higher education of women.
In December 1859 he wrote critically of the unpopularity of John Bright. He was closely identified with the Sunday League, was its president in 1879, and inaugurated the popular lectures for Sunday evenings.
He also supported the Sunday opening of museums and picture-galleries, to promote which the Sunday Society was formed in 1875.
From 1862 Slack edited the Intellectual Observer, a development of a journal called Recreative Science, founded in 1859. From 1868 to 1871 it continued as The Student. An amateur microscopist, he was successively secretary and, in 1878, president of the Royal Microscopical Society.
Between 1858 and 1869 he lived at 34 Camden Square, London.
He died at his home, Forest Row, Sussex, on 16 June 1896. Slack was admitted to the Middle Temple in 1850.
In 1868 he was introduced to William Michael Rossetti, as a "legal gentleman", leading to some opaque dealings with a role in literary history. Slack lent to Rossetti some letters of Percy Bysshe Shelley, which had been part of a correspondence in his early life with Elizabeth Hitchener.
The story Slack told about how the letters had come into his possession was that he had had them from H. Holste, solicitor and executor to Hitchener who died in 1822.
Rossetti was interested in publishing poems occurring in the letters, in particular To Mary who Died. Wise, however, unauthorised, published the letters. The letters had been deposited with Slack, on conditions that are unclear.
lieutenant is also unclear why they were deposited, given that Slack was not a lawyer
And he did not claim he owned them. He gave an indication of the owner as a lady living in Germany.
The original letters passed from Slack"s widow as a legacy to Charles Hargrove. From him they went to the British Museum in 1907, and so to the British Library.
He was a Cobdenite, and a member of the National Education League.