For some reason, probably its darkness, the ‘spacious covered piazza’ on the ground floor of the Town Hall was not acceptable to the merchants, who preferred to do their business in the open street in front, in spite of all the inconveniences resulting from the traffic of a busy town. Then William Roscoe is said to have outlined the plan of the Exchange Buildings – to clear away all the houses around the Town Hall to the north and surround three sides of the area so opened out by a block of commercial buildings harmonising with the Town Hall, which would form a fourth side, though separated by streets at each corner. In 1881 there was a Determined Fenian attempt to blow up the Town Hall by dynamite. At the trial it was ascertained that the conspirators had a few days previously attempted to blow up the Police Station, Hatton Garden; fortunately no lives were lost. The prisoner M'Grath was sentenced to penal servitude for life, and the prisoner M'Kevitt to 15 years. The police officers who were instrumental in their capture were rewarded.