An 18 pounder shell from the 1916 Rising has come in to the artifacts on display from the Irish Volunteers Commemorative Organisation.
During the 1916 Rising ,the Irish Volunteers entrenched themselves in many buildings,the British decided to use artillery to root them out.
From Wednesday on, Liberty Hall, the GPO and other buildings in Sackville Street came under artillery and incendiary ﬁre, mostly from the gunboat Helga at anchor in the Liﬀey. The Imperial Hotel located over Clery’sdepartment store, across the street from the GPO, was one of the ﬁrst buildings to be set on ﬁre; soon most buildings between that and the Liﬀey were in ﬂames. Connolly had naively believed that the British would not use artillery in city areas because as capitalists they would be reluctant to destroy property(National Library of Ireland)
The National Graves Association said in 2003: “On April 23, 1916, some 150 insurgents took over the GPO in Dublin and the men and women fought without pause or sleep for five days and nights.
“Ravaged by sniper fire, machine guns, nine-pound guns from Trinity College and 18-pound shells from the gunboat the Helga, the insurgents were forced to abandon the GPO and set up headquarters in 16 Moore Street.”
Their main firepower was provided by the gunboat Helga and field artillery(namely 18 pounder artillery guns,IVCO) summoned from their garrison at Athlone which they positioned on the north side of the city at Prussia Street, Phibsborough and the Cabra road. These guns shelled large parts of the city throughout the week and burned much of it down. (The first building shelled was Liberty Hall, which ironically had been abandoned since the beginning of the Rising.) Interestingly the Helga’s guns had to stop firing as the elevation necessary to fire over the railway bridge meant that her shells were endangering the Viceregal Lodge in Phoenix Park, (Helga was later bought by the government of the Irish Free State, and was the first ship in its navy).(New World encyclopedia)
18 Pounder Field Gun in action (wikipedia)