A rook rifle, as the name suggests, was used for shooting rooks – regarded in the 19th century as pests and vermin – along with small game such as rabbits or hares.

It was never intended to shoot people, but needs must in a revolution and in 1919 the IRA was desperate for weapons that could be used against the British in the War of Independence.

One such gun was discovered wrapped in an old newspaper by Laurence Callery, of the Callery construction company, while carrying out renovation work on the kitchen of a neighbour’s house at St Teresa’s Place in Glasnevin, Dublin.

The house owners, Paul and Caroline Martin, were on holiday in Portugal at the time. Mr Callery discovered the gun in a hidden alcove under the stairs.

“It was found in the type of place where you’d never go near or touch. I still feel a bit weird holding it when you consider what it might have been used for,” said Mr Martin.

It is likely that the rifle was being kept for less innocent designs than shooting rooks or rabbits. The newspaper was the now defunct Lloyd’s Sunday News and the date was August 10th, 1919, at a time when the IRA was ramping up its campaign of undermining British authority in Ireland.

The Dublin Metropolitan Police regularly raided the homes of those they suspected of being members of the IRA and the gun may have been put out of sight for safekeeping.

Interned

He went on to become a solicitor and was appointed a district judge in 1948. He died in 1969.

Mr Martin took the rook rifle to Lar Joye, the curator of Irish military history at the National Museum, Collins Barracks.

Mr Joye said the gun was of a very low calibre: “It was the runt of the litter of guns.” However, the IRA was so short of munitions that every kind of weapon was pressed into use, including 19th century muskets.

Rook rifles were first introduced in 1888 for gamekeepers and were discontinued after the second World War.

The gun is obsolete – it has a firing pin but no flint. Even if it could be fired, there is no longer any suitable ammunition.