An Cosantóir

www.military.ie the defence forces magazine | 31 James O'Donovan, a post-graduate chemistry student at UCD who worked directly for Collins, was the primary chemist/inven- tor of explosives for the IRA, and the person most responsible for developing and establishing Irish explosive manufacturing. In 1918 he had begun producing explosives from fulminate of mer- cury a notoriously unstable compound – but in 1919 Collins directed him to develop an explosive that was more powerful, but one that "men with no technical skill could produce in a farmhouse kitchen". "They have to be fairly fool proof," Collins said, "because we can't have people all over the country having their heads blown off!" 'Irish War Flour' was O'Donovan's original explosive (named after its appearance), made from resin, flour, acid and potassium chlorate. However, it was quite unstable and didn't have the explosive power he wanted so he kept experimenting. He called his second explosive compound Irish Cheddar, which was his nickname for a form of cheddite, an explosive used quite extensively in the early 20th century made from paraffin, potas- sium chlorate, nitrobenzene and castor oil. The first attempt at a road mine took place at Annascaul on 18th August 1920 when the IRA detonated a small mine that turned over a lorry; the British surrendered and the Irish took their weapons. From autumn 1920 there was an increase in IRA road and bridge attacks, and they also began to regularly use what we now call IEDs in ambushes. The British War Diaries report 172 ambushes from then until the Truce in July 1921, including the use of 109 explosive devices of some sort. When British tactics changed by stretching the length of its columns to make it difficult to attack them without deploying a large force, the IRA quickly learned the trick of laying multiple roadside IEDs at the same spacing as the British vehicles in a con- voy – usually 300 yards apart. However, proper placement of IEDs was difficult for inexpe- rienced IRA volunteers, who had little enough training in how to conduct ambushes and placing men, much less how to use explosives in these attacks. Therefore, as the war progressed the Irish found that their IEDs were best initiated not by pressure or contact, but with electrical detonators attached to wires buried in the road so that they could be exploded by command just when they were crossed by a lorry or armoured car. The first major IRA attack with what we would now recog- nise as an IED with sufficient explosive power to bring a quick result was on 2nd February 1921 in Clonfin, County Longford, where an ambush party under the command of Sean MacEoin attacked two lorries of Auxiliaries, disabling one, and killing four and wounding nine of the Auxiliaries. After a short firefight the remainder surrendered and the Irish recovered 20 rifles and over 1,200 rounds of ammunition. By the time of the Truce, the IRA had 11 foundries making bomb components, and Collins also had his engineers working on producing armour-piercing ammunition – his sources couldn't buy them at any price – although they never managed to succeed. Due to the unreliable explosives available and the lack of expe- rience in their use, there were few ambushes where the IEDs were crucial, rather than ancillary, to the attack. However, it still stands that the Irish War of Independence introduced the IED and the car bomb to the catalogue of guerrilla war tactics. And the use of explosives did not stop with the end of the War of Independence; during the Civil War, on 18th August 1922, a fuel delivery lorry packed with explosives was detonated in Dundalk in an attempt to stop the Free State army, who were marching on Dundalk barracks, which had been taken over by anti-Treaty forces, under Frank Aiken. Recent books by Joseph EA Connell Jnr about the author: Joseph E.A. Connell Jnr is a US na- tive and the author of a number of books on Dublin and its revolutionary history. His recent books are Dublin Rising 1916 and Who's Who In The Dublin Rising 1916. His latest book is Michael Collins: Dublin 1916-22, published in April 2017 by www.wordwellbooks.com James O'Donovan IRA Director of Chemicals.

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