Question: Who is the paternal grandfather of Jacob Pleydell-Bouverie, 4Th Earl Of Radnor?

Knowledge 1: Jacob Pleydell-Bouverie, 4th Earl of Radnor
Jacob Pleydell-Bouverie, 4th Earl of Radnor (18 September 1815 – 11 March 1889), was the son of William Pleydell-Bouverie, 3rd Earl of Radnor and JudithAnne St John-Mildmay.He was styled Viscount Folkestone from 1828 until 1869.Folkestone was educated at Harrow and Christ Church, Oxford.On 2 October 1837, he was commissioned a cornet in the Salisbury Troop of the Royal Wiltshire Regiment of Yeomanry.He was a lieutenant in the Regiment from 20 May 1840 to April 1847.He married Lady Mary Augusta Frederica Grimston, daughter of James Walter Grimston, 1st Earl of Verulam, on 3 October 1840.They had twelve children:Folkestone was appointed High Sheriff of Wiltshire in 1846 and a deputy lieutenant of Berkshire on 2 May 1855.He succeeded his father as Earl of Radnor in 1869 and was appointed Lord Lieutenant of Wiltshire in 1878.Radnor served as Governor of the French Hospital.Successive Earls of Radnor were governors of the hospital from the eighteenth century to 2015. [SEP] Knowledge 2: William Pleydell-Bouverie, 3rd Earl of Radnor
William Pleydell-Bouverie, 3rd Earl of Radnor (11 May 1779 – 9 April 1869), styled Viscount Folkestone until 1828, was the son of Jacob Pleydell-Bouverie, 2nd Earl of Radnor and Hon.Anne Duncombe.He first entered the House of Commons for Downton upon reaching his majority in 1801, switching to Salisbury in 1802.He was appointed a deputy lieutenant of Berkshire on 22 November 1801.He married, firstly, Lady Catherine Pelham-Clinton (d. 17 May 1804), daughter of Henry Pelham-Clinton, Earl of Lincoln, on 2 October 1801 and had two children:On 31 March 1803, he was commissioned a captain in the Berkshire Regiment of Militia, and a captain in the Berkshire Yeomanry on 14 March 1805.From 9 December 1812 to August 1817, he was lieutenant-colonel of the Berkshire Regiment of Militia.He married, secondly,Judith Anne St John-Mildmay, daughter of Sir Henry St John-Mildmay, 3rd Baronet on 24 May 1814 and had six children:On 27 January 1828, he succeeded his father as Earl of Radnor, and on 9 February 1828 as Recorder of Salisbury.Radnor was made a deputy lieutenant of Wiltshire on 9 August 1839 and a vice-lieutenant of the county on 17 August 1839.In 1828, he built a toll road providing an easy route between Folkestone harbour and Sandgate.The original toll house remains within the Lower Leas Coastal Park.Either side of the toll road, land was cultivated and grazed.Old field boundaries are still used in the park, and the 'Cow Path' is a reminder of the drove route from The Leas.Radnor served as governor of the French Hospital at the time of its move from Finsbury to the new and imposing hospital building in Victoria Park, Hackney, designed by Robert Lewis Roumieu.Successive Earls of Radnor were governors of the hospital from the eighteenth century to 2015.
Knowledge 1: William Pleydell-Bouverie, 3rd Earl of Radnor
William Pleydell-Bouverie, 3rd Earl of Radnor (11 May 1779 – 9 April 1869), styled Viscount Folkestone until 1828, was the son of Jacob Pleydell-Bouverie, 2nd Earl of Radnor and Hon.Anne Duncombe.He first entered the House of Commons for Downton upon reaching his majority in 1801, switching to Salisbury in 1802.He was appointed a deputy lieutenant of Berkshire on 22 November 1801.He married, firstly, Lady Catherine Pelham-Clinton (d. 17 May 1804), daughter of Henry Pelham-Clinton, Earl of Lincoln, on 2 October 1801 and had two children:On 31 March 1803, he was commissioned a captain in the Berkshire Regiment of Militia, and a captain in the Berkshire Yeomanry on 14 March 1805.From 9 December 1812 to August 1817, he was lieutenant-colonel of the Berkshire Regiment of Militia.He married, secondly,Judith Anne St John-Mildmay, daughter of Sir Henry St John-Mildmay, 3rd Baronet on 24 May 1814 and had six children:On 27 January 1828, he succeeded his father as Earl of Radnor, and on 9 February 1828 as Recorder of Salisbury.Radnor was made a deputy lieutenant of Wiltshire on 9 August 1839 and a vice-lieutenant of the county on 17 August 1839.In 1828, he built a toll road providing an easy route between Folkestone harbour and Sandgate.The original toll house remains within the Lower Leas Coastal Park.Either side of the toll road, land was cultivated and grazed.Old field boundaries are still used in the park, and the 'Cow Path' is a reminder of the drove route from The Leas.Radnor served as governor of the French Hospital at the time of its move from Finsbury to the new and imposing hospital building in Victoria Park, Hackney, designed by Robert Lewis Roumieu.Successive Earls of Radnor were governors of the hospital from the eighteenth century to 2015. [SEP] Knowledge 2: Gerald Barry (British Army officer)
Gerald Barry MC (18 December 1896 – 21 February 1977) was a career officer in the British Army who played in one first-class cricket match for the Combined Services against Essex.In the match, played at Leyton in May 1922, Barry batted at No 10 in the Services team's two innings and scored only two runs, and opened the bowling in each Essex innings without taking a wicket.He did not play first-class cricket again.Barry was educated at Eton College, from which he joined the Coldstream Guards in the First World War.He was awarded the Military Cross.He later rose to the tank of lieutenant colonel in the Black Watch.During the Second World War, his postings included deputy military secretary of the Eastern Army in India.Barry married Lady Margaret Pleydell-Bouverie, daughter of Jacob Pleydell-Bouverie, 6th Earl of Radnor in 1923.They had five daughters and one son.His brother-in-law was Nigel Capel-Cure, who also played one first-class cricket match.
Knowledge 1: Jacob Pleydell-Bouverie, 4th Earl of Radnor
Jacob Pleydell-Bouverie, 4th Earl of Radnor (18 September 1815 – 11 March 1889), was the son of William Pleydell-Bouverie, 3rd Earl of Radnor and JudithAnne St John-Mildmay.He was styled Viscount Folkestone from 1828 until 1869.Folkestone was educated at Harrow and Christ Church, Oxford.On 2 October 1837, he was commissioned a cornet in the Salisbury Troop of the Royal Wiltshire Regiment of Yeomanry.He was a lieutenant in the Regiment from 20 May 1840 to April 1847.He married Lady Mary Augusta Frederica Grimston, daughter of James Walter Grimston, 1st Earl of Verulam, on 3 October 1840.They had twelve children:Folkestone was appointed High Sheriff of Wiltshire in 1846 and a deputy lieutenant of Berkshire on 2 May 1855.He succeeded his father as Earl of Radnor in 1869 and was appointed Lord Lieutenant of Wiltshire in 1878.Radnor served as Governor of the French Hospital.Successive Earls of Radnor were governors of the hospital from the eighteenth century to 2015. [SEP] Knowledge 2: Gerald Barry (British Army officer)
Gerald Barry MC (18 December 1896 – 21 February 1977) was a career officer in the British Army who played in one first-class cricket match for the Combined Services against Essex.In the match, played at Leyton in May 1922, Barry batted at No 10 in the Services team's two innings and scored only two runs, and opened the bowling in each Essex innings without taking a wicket.He did not play first-class cricket again.Barry was educated at Eton College, from which he joined the Coldstream Guards in the First World War.He was awarded the Military Cross.He later rose to the tank of lieutenant colonel in the Black Watch.During the Second World War, his postings included deputy military secretary of the Eastern Army in India.Barry married Lady Margaret Pleydell-Bouverie, daughter of Jacob Pleydell-Bouverie, 6th Earl of Radnor in 1923.They had five daughters and one son.His brother-in-law was Nigel Capel-Cure, who also played one first-class cricket match.

Answer: Jacob Pleydell-Bouverie, 2nd Earl of Radnor