Question: The great grandson of the Liberal prime minister William Ewart Gladstone, and brother of Sir William Gladstone, competed in what event between Oxford University and Cambridge University on the River Thames?

Context paragraphs:
Henry Gladstone, 1st Baron Gladstone of Hawarden: Henry Neville Gladstone, 1st Baron Gladstone of Hawarden (2 April 1852 – 28 April 1935) was a British businessman and politician.  He was the third son of Prime Minister William Ewart Gladstone.

The Boat Race: The Boat Race is an annual rowing race between the Oxford University Boat Club and the Cambridge University Boat Club, rowed between men's open-weight eights on the River Thames in London, England.  It is also known as the University Boat Race and the Oxford and Cambridge Boat Race.

Gladstone (cat): Gladstone is the resident Chief Mouser of HM Treasury at Whitehall, London.  He is a domestic short-haired cat, who, at eighteen months old, assumed the position of Chief Mouser in late June 2016.  Gladstone's political namesake is former Chancellor and Prime Minister William Ewart Gladstone who served for four separate periods, more than any other Prime Minister.  The hope is Gladstone will control mice at the Treasury's 1 Horse Guards Road building.

Peter Gladstone: Peter Gladstone (16 October 1928 – 25 July 2000) was a British naturalist and wildfowl expert.  He was the great grandson of the Liberal prime minister William Ewart Gladstone, and brother of Sir William Gladstone, 7th Baronet.  He grew up at Hawarden Castle in Wales, and attended Eton College, where his father, Charles Gladstone, was a housemaster.  He served in the Palestine Police in 1946, towards the end of the British Mandate of Palestine.  From 1949 to 1952 he studied biology at Christ Church, Oxford, and rowed for Oxford in the 1952 Boat Race.  He went on to teach biology at Shrewsbury School until 1971, when he joined Sir Peter Scott's Wildfowl and Wetlands Trust.  Gladstone developed the trust's wildfowl reserve at Martin Mere in Lancashire.  In the 1970s he took over the management of Fasque House, a family property in Aberdeenshire.  In 1998 he journeyed to Tibet in an unsuccessful search for the pink-headed duck.  He was a fellow of the Royal Geographical Society.  Gladstone died of a heart attack at the age of 71.

Gladstone baronets: The Gladstone Baronetcy, of Fasque and Balfour in the County of Kincardine, is a title in the Baronetage of the United Kingdom.  It was created on 18 July 1846 for the Scottish businessman and politician John Gladstone, father of prime minister William Ewart Gladstone.  Born John Gladstones, the son of the merchant Thomas Gladstones, John assumed by Royal licence the surname of Gladstone (without the "s" at the end) in 1835.  The name Gladstone is geographical, deriving from a farmstead near Biggar in Lanarkshire; it comes from the Old English for "kestrel stone".

Cardwell Reforms: The Cardwell Reforms refer to a series of reforms of the British Army undertaken by Secretary of State for War Edward Cardwell between 1868 and 1874 with the support of Liberal prime minister William Ewart Gladstone.  Gladstone paid little attention to military affairs but he was keen on efficiency.  In 1870, he pushed through Parliament major changes in Army organisation.  Germany's stunning triumph over France in the Franco-Prussian War proved that the Prussian system of professional soldiers with up-to-date weapons was far superior to the traditional system of gentlemen-soldiers that Britain used.

Sir Stephen Glynne, 9th Baronet: Sir Stephen Richard Glynne, 9th Baronet (22 September 1807 – 17 June 1874) was a Welsh landowner and Conservative Party politician.  He is principally remembered as an assiduous antiquary and student of British church architecture.  He was a brother-in-law of the Liberal Prime Minister William Ewart Gladstone.

Sir John Gladstone, 1st Baronet: Sir John Gladstone of Fasque, 1st Baronet, FRSE LLD (11 December 1764 – 7 December 1851) was a Scottish merchant, slave-trader, Member of Parliament, and the father of the British Prime Minister William Ewart Gladstone.  Through his commercial activities he acquired several large plantations in Jamaica and Guyana, worked initially by enslaved Africans.  As a result of the Slavery Abolition Act 1833 which abolished slavery in the British Empire, Gladstone expelled most African workers from his estates and imported large numbers of indebted Indian indentured-servants, through false promises of providing them schools and medical attention.  However, upon arrival they were paid no wages, the repayment of their debts being deemed sufficient, and worked under conditions that continued to resemble slavery in everything except name.  Active in politics he worked to secure compensation from the British Government for "property losses" (in this case slaves) incurred as a result of the Slavery Abolition Act 1833 and eventually received £106,769 (modern equivalent £83m),

Sir John Gladstone, 3rd Baronet: Sir John Robert Gladstone, 3rd Baronet (26 April 1852 – 25 June 1926) was the son of Sir Thomas Gladstone, an older brother of the Liberal Prime Minister William Ewart Gladstone, and Louisa Fellowes.

Glynne baronets: The Glynne Baronetcy, of Bisseter in the County of Oxford, was a title in the Baronetage of England.  It was created on 20 May 1661 for William Glynne, the former Member of Parliament for Carnarvon.  He was the son of Sir John Glynne, Lord Chief Justice during the Commonwealth.  The second Baronet sat as Member of Parliament for Oxford University and Woodstock.  The sixth Baronet was Member of Parliament for Flintshire and Flint.  The title became extinct on the death in 1874 of Sir Stephen Glynne, 9th Baronet.  The family estates, including Hawarden Castle in Flintshire, had been rescued from bankruptcy by the wealth of Sir John Gladstone, whose son William Ewart Gladstone (the Liberal Prime Minister) had married the ninth Baronet's sister Catherine; on his death, they passed to Catherine and William's eldest son William Henry Gladstone.

Supporting paragraphs: Peter Gladstone The Boat Race
Answer: The Boat Race