A group of Sheffield Chartists led by Samuel Holberry had collected weapons. They planned to meet and seize the Town Hall and the Fortune Inn, besides setting fire to magistrates’ houses. They were to be backed by men from Eckington, Rotherham and Barnsley, while riots were to take place in Nottingham and Dewsbury. Much secrecy surrounded the plan, and Holberry threatened to kill anyone who backed out. The plot was betrayed by James Allen, the landlord of the Station Inn, Rotherham. He overheard some of the plans and reported them to John Bland (the Chief Constable of Barnsley) and to Lord Howard (the Lord Lieutenant). Many arrests were made, including Holberry, who was sentenced to four years’ imprisonment. Allen was forced to leave the country, while Bland and Howard kept their roles quiet. In February 1840, five hundred special constables were sworn in at Sheffield alone to deter threats of rioting. R.G. Gammage, author of History of the Chartist Movement 1838-1853, writing in 1854, said:
“At Sheffield things began to look ominous. Large meetings assembled in the open air at night, at which not a word was spoken. Several persons were arrested in connection with these meetings, which were dispersed by the military.” Gammage takes the story forward: “About the same time [January 1840] a large number of the Chartists of Sheffield were arrested for conspiracy and administering illegal oaths. The principal witnesses against them were persons who professed to have been engaged with them in the conspiracy. One Thompson deposed that a large number of persons were formed into classes, and that they had provided themselves with arms, and fixed upon a plan for taking some, and firing other, parts of the town. That they had agreed to strike down every policemen and watchman that they might meet, and catch the soldiers before they could fire upon them. The barracks were to be fired, and the insurgents were to possess themselves of the Town Hall and Tontine, which they were to defend with the barricades. After the evidence had been given, Samuel Holberry, William Booker, Thomas Booker, John Clayton, Samuel Bentley, John Marshall, Thomas Penthorpe, Joseph Bennison, and William Wells, were fully committed for trial, Mrs Holberry, a very interesting woman, was also arrested; but the evidence against her not being sufficient, she was discharged.”
In the mean time, a further uprising was thwarted at Bradford, and further arrests were made. Gammage says of the trial: “On Monday, March the 16th , the Yorkshire assizes commenced, before Mr Justice Erskine and Mr Justice Coleridge when the Sheffield Chartists were brought to trial. The court presented from the outset a very animated appearance; the gentlemen of the legal profession attending in large numbers both for and against the prisoners. Holberrry, the two Bookers, Duffy and Wells were first indicted for conspiracy and riot. By way of supporting the evidence against the prisoners, a large basket full of hand-grenades, and other combustible materials, was placed upon the table, and a great number of pikes and daggers were also produced. The evidence went to prove that these were found in possession of the prisoners at the time of their arrest. The charges appeared to weigh most heavily against Holberry, who did not, when arrested, deny, but on the contrary, admitted, that his object was to upset the Government, and he professed his willingness to die for the Charter. The principal witnesses for the prosecution were Foxhall and Thompson, who were admitted as Queen’s evidence, and who had taken an active part in the proceedings of the accused. The Attorney General prosecuted, and Sir Gregory Lewin, Mr Watson, and Mr Murphy defended the prisoners, and dealt in strong terms on the evidence of the witnesses; but after Justice Erskine had summed up, the jury found all the prisoners guilty. William Wells, John Clayton, John Marshall, Thomas Penthorpe, Joseph Bennison, and Charles Fox were charged with similar offences, and pleaded guilty. Robert Cox, George Gullimore, James Bartholomew, Joseph Lingard, Thomas Powls, and Joshua Clayford, who had been out on bail, were also indicted for riot and conspiracy. Mr Baines and Mr Wortley prosecuted; Mr Murphy and Mr Wilkins defended the prisoners in able addresses, and succeeded in procuring a verdict of acquittal. John Marsden was indicted for riot, and attempting to liberate from prison Peter Foden, one of the arrested Chartists, to which charge he pleaded guilty. William Martin was indicted for sedition. Messrs Baines and Wortley conducted the prosecution. The prisoner was most eloquently defended by Mr Watson, but the result was a verdict of guilty.
The assizes continued, with Feargus O’Connor next up before the court to face charges of newspaper libel. According to Hovell: “He called, or proposed to call, fifty witnesses to prove that he had never advocated physical force, though it does not appear that this point was at all material to the question. He was condemned to eighteen months’ imprisonment, but actually served only ten, being released on account of bad health.”
The Bradford Chartists then faced the court charged with offences of riot and conspiracy. Gammage says: “On the 21st of March the Sheffield and Bradford prisoners were brought up to receive sentence. Holberry was sentenced to four years’ imprisonment, and bound over in fifty pounds, and two sureties of ten pounds each, to keep the peace after the term of his imprisonment should expire. Thomas Booker was sentenced to three years’ imprisonment, and bound to keep the peace in thirty pounds, and two sureties of ten pounds each. William Booker, his son, was imprisoned for two years, and bound over to keep the peace in the sum of twenty pounds. James Duffy was sentenced to three years’ imprisonment, and bound over in the sum of twenty pounds and two sureties of ten pounds each. William Wells received a sentence of one year’s imprisonment, and was bound over in the sum of twenty pounds. Marshall, Penthorpe, and Bennison, were each sentenced to two years’ imprisonment.
 On Samuel Holberry (1814-1842), see Joyce M. Bellamy and John Saville (eds.) Dictionary of Labour Biography volume iv, Macmillan, 1977, pages 93-96.
 R.G. Gammage History of the Chartist Movement 1838-1853, 1854, page 153.
 R.G. Gammage History of the Chartist Movement 1838-1853, 1854, page 173.
 R.G. Gammage History of the Chartist Movement 1838-1853, 1854, page 175.
 Mark Hovell The Chartist Movement, Manchester University Press, 1918, page 187.
 R.G. Gammage History of the Chartist Movement 1838-1853, 1854, page 177.