Question: Who is the paternal grandfather of Charles Bruce, 5Th Earl Of Elgin?

Knowledge 1: Charles Bruce, 5th Earl of Elgin
Charles Bruce, 5th Earl of Elgin and 9th Earl of Kincardine (6 July 1732 – 14 May 1771) was the son of William Bruce, 8th Earl of Kincardine.His mother was Janet Roberton, daughter of James Roberton (principal Lord of Session) and great-granddaughter of advocate and judge Lord BedlayOn 1 June 1759, he married Martha Whyte (1739-1810, who later became governess to Princess Charlotte of Wales.They had eight children:Elgin was Grand Master of Scottish Freemasons from 1761 to 1763 and a founding member of the Royal and Ancient Golf Club of St Andrews.He built the planned industrial village of Charlestown, Fife.He is buried in the southern transept of Dunfermline Abbey close to the grave of Robert the Bruce. [SEP] Knowledge 2: William Bruce, 8th Earl of Kincardine
William Bruce, 8th Earl of Kincardine (died 8 September 1740), the son of Thomas Bruce, 7th Earl of Kincardine and Rachel Paunceforth, became the 8th Lord of Torry and the 8th Earl of Kincardine in 1740.His wife was Janet Roberton, the daughter of James Roberton, a Lord of Session (in turn a grandson of James Roberton,Lord Bedlay an ordinary Lord of Session during the Restoration.)and his wife Euphemia Burnett.The couple were second cousins, both descendants of Robert Bruce, Lord Broomhill.Bruce’s descent was through his father Thomas Bruce 7th Earl of Kincardine and his grandfather Alexander 4th Earl of Kincardine.His wife’s mother was the daughter of Janet Bruce, Alexander’s sister.Bruce had five children:
His son Charles Bruce inherited the Earldom of Elgin from the extinct line of Charles Bruce, the 3rd Earl of Ailesbury and 4th Earl of Elgin by virtue of their descent from Sir George Bruce, younger brother of Edward, the 1st Lord of Kinloss
Knowledge 1: Charles Bruce, 5th Earl of Elgin
Charles Bruce, 5th Earl of Elgin and 9th Earl of Kincardine (6 July 1732 – 14 May 1771) was the son of William Bruce, 8th Earl of Kincardine.His mother was Janet Roberton, daughter of James Roberton (principal Lord of Session) and great-granddaughter of advocate and judge Lord BedlayOn 1 June 1759, he married Martha Whyte (1739-1810, who later became governess to Princess Charlotte of Wales.They had eight children:Elgin was Grand Master of Scottish Freemasons from 1761 to 1763 and a founding member of the Royal and Ancient Golf Club of St Andrews.He built the planned industrial village of Charlestown, Fife.He is buried in the southern transept of Dunfermline Abbey close to the grave of Robert the Bruce. [SEP] Knowledge 2: James Bruce (1769–1798)
James Bruce( 1769 –1798) was a Member of Parliament for Marlborough in the Parliament of Great Britain from 1796 until 1797.The youngest of the five sons of Charles Bruce, 5th Earl of Elgin, and of Martha Bruce, Countess of Elgin and Kincardine( 1739 – 1810), Bruce was a brother of the collector Thomas Bruce, 7th Earl of Elgin, known for bringing the Elgin Marbles from Athens.He entered Westminster School in 1778 and was at Christ Church, Oxford, from 1786 to 1790, when he became a member of Lincoln's Inn.For a year he was a Member of Parliament for Marlborough, taking a seat previously held by his uncle General Thomas Bruce, before resigning by" taking the Chiltern Hundreds".He left parliament to accept a post as a" précis" writer at the Foreign Office at a salary of £ 300 a year.On 10 July 1798, aged only twenty- nine, he was drowned while crossing the River Don at Barnby Dun in Yorkshire, when his horse was swept away by the stream.He was remembered as amiable and virtuous.
Knowledge 1: William Bruce, 8th Earl of Kincardine
William Bruce, 8th Earl of Kincardine (died 8 September 1740), the son of Thomas Bruce, 7th Earl of Kincardine and Rachel Paunceforth, became the 8th Lord of Torry and the 8th Earl of Kincardine in 1740.His wife was Janet Roberton, the daughter of James Roberton, a Lord of Session (in turn a grandson of James Roberton,Lord Bedlay an ordinary Lord of Session during the Restoration.)and his wife Euphemia Burnett.The couple were second cousins, both descendants of Robert Bruce, Lord Broomhill.Bruce’s descent was through his father Thomas Bruce 7th Earl of Kincardine and his grandfather Alexander 4th Earl of Kincardine.His wife’s mother was the daughter of Janet Bruce, Alexander’s sister.Bruce had five children:
His son Charles Bruce inherited the Earldom of Elgin from the extinct line of Charles Bruce, the 3rd Earl of Ailesbury and 4th Earl of Elgin by virtue of their descent from Sir George Bruce, younger brother of Edward, the 1st Lord of Kinloss [SEP] Knowledge 2: James Bruce (1769–1798)
James Bruce( 1769 –1798) was a Member of Parliament for Marlborough in the Parliament of Great Britain from 1796 until 1797.The youngest of the five sons of Charles Bruce, 5th Earl of Elgin, and of Martha Bruce, Countess of Elgin and Kincardine( 1739 – 1810), Bruce was a brother of the collector Thomas Bruce, 7th Earl of Elgin, known for bringing the Elgin Marbles from Athens.He entered Westminster School in 1778 and was at Christ Church, Oxford, from 1786 to 1790, when he became a member of Lincoln's Inn.For a year he was a Member of Parliament for Marlborough, taking a seat previously held by his uncle General Thomas Bruce, before resigning by" taking the Chiltern Hundreds".He left parliament to accept a post as a" précis" writer at the Foreign Office at a salary of £ 300 a year.On 10 July 1798, aged only twenty- nine, he was drowned while crossing the River Don at Barnby Dun in Yorkshire, when his horse was swept away by the stream.He was remembered as amiable and virtuous.

Answer: Thomas Bruce, 7th Earl of Kincardine