From Wikipedia: Leonard Darwin

Leonard Darwin FRGS [Fellow of the Royal Geographical Society] (Tuesday, 15 January 1850 – Friday, 26 March 1943) was an English politician, economist and eugenicist. He was a son of the naturalist Charles Darwin, and also a mentor to Ronald Fisher, a statistician and evolutionary biologist.

Biography

Leonard Darwin was born in 1850 at Down House, Luxted Road, Downe, Kent BR6 7JT 51.33139, 0.05333, into the wealthy Darwin–Wedgwood family. He was the fourth son and eighth child of the naturalist Charles Darwin and his wife Emma Wedgwood, and the last of Darwin's immediate offspring to die. He considered himself the least intelligent of their children – brothers Frank, George and Horace were all elected Fellows of the Royal Society. He was sent to Clapham School in 1862.

Darwin joined the Royal Engineers in 1871. Between 1877 and 1882 he worked for the Intelligence Division of the Ministry of War. He went on several scientific expeditions, including those to observe the Transit of Venus in 1874 and 1882.

In 1890, Darwin was promoted to the rank of major, but soon left the army and from 1892 to 1895 was a Liberal Unionist Member of Parliament (MP) for Lichfield constituency in Staffordshire, where his grandfather, Josiah Wedgwood II, had also been an MP. He wrote vigorously on the economic issues of the day: bimetallism, Indian currency reform and municipal trade.

Darwin married Elizabeth Frances Fraser on Tuesday, 11 July 1882. She died 16 years later, on Thursday, 13 January 1898. On Thursday, 29 November 1900, he married his second cousin, Charlotte Mildred Massingberd, granddaughter of Charlotte Wedgwood, his mother's sister. Their shared ancestor was Josiah Wedgwood II. His wife Charlotte's paternal grandfather married his paternal aunt, after her grandmother Charlotte's death. Since Leonard's parents were cousins, Charlotte was also a second cousin on his father's side. Leonard had no children from either marriage.

He was president of the Royal Geographical Society from 1908 to 1911 and chairman of the British Eugenics Society from 1911 to 1928 – succeeding his half-cousin once removed Francis Galton. He became the society's honorary president in 1928. In 1912 the University of Cambridge conferred on him an honorary doctorate of science.

Darwin played an important part in the life of the geneticist and statistician Ronald Fisher, supporting him intellectually, morally and sometimes financially. Fisher, replying to Darwin's congratulations on his election to the Royal Society, replied on Monday, 25 February 1929, "I knew you would be glad, and your pleasure is as good to me almost as though my own father were still living."

Some years before, Fisher had resigned from the Royal Statistical Society after a disagreement. Darwin regretted this and engineered Fisher's re-entry by making him a gift of a life-time subscription. Fisher's 1930 book The Genetical Theory of Natural Selection is dedicated to Darwin. After Darwin's death in 1943 at the age of 93, Fisher wrote to Darwin's niece, Margaret Keynes, "My very dear friend Leonard Darwin... was surely the kindest and wisest man I ever knew."

Darwin retired to Cripps Corner at Forest Row, East Sussex in 1921, with his second wife Charlotte Mildred Massingberd (died 1940), and lived there until his death in 1943. He and Charlotte were buried at Forest Row Cemetery. Leonard Darwin was the last surviving child of Charles Darwin.

Publications

• Author of Bimetallism: a summary and examination of the arguments for and against a bimetallic system of currency by Major Leonard Darwin Published 1897
• Author of The questions to be considered by the Indian Currency Committee by Major Leonard Darwin Published 1898
• Author of British expansion in West Africa Major Leonard Darwin Published 1899
• Author of Municipal Trade: the advantages and disadvantages resulting from the substitution of representative bodies for private proprietors in the management of industrial undertakings by Major Leonard Darwin Published 1903
• Author of Organic evolution: outstanding difficulties and possible explanations by Major Leonard Darwin Published 1921
• Author of Some birth rate problems by Major Leonard Darwin Published 1921
• Author of The need for eugenic reform, by Leonard Darwin Published 1926
• Author of What is eugenics? by Major Leonard Darwin Published 1928

From FreeBMD: Registration of birth of Leonard Darwin in 1850

January to March 1850: Registration of birth of Leonard Darwin; in Bromley, Kent (Volume V, Page 59)

From Wikipedia: 1874 Transit of Venus Expedition to Hawaii

The 1874 Transit of Venus Expedition to Hawaii was an astronomical expedition by British scientists to observe the Tuesday, 8 December 1874 transit of Venus at three separate observing sites in the Hawaiian Islands, then known as the Sandwich Islands. It was one of five 1874 transit expeditions organized by George Biddell Airy, Astronomer Royal at the Royal Observatory, Greenwich. The purpose of the expedition was to obtain an accurate estimate of the astronomical unit (AU), the distance from the Earth to the Sun, by measuring solar parallax. Previous efforts to obtain a precise value of an AU in 1769 had been hampered by the black drop effect. There is a collection of papers relating to this expedition at the Cambridge Digital Library.

Team

... Charles Darwin's son, Leonard Darwin, was a photographer on the 1874 Transit of Venus Expedition to New Zealand, after which he travelled to Hawaii aboard the Mikado to meet the team in Honolulu.

From FreeBMD: Registration of marriage of Charlotte Mildred Langton in 1900 and FreeBMD: Registration of marriage of Leonard Darwin in 1900

• October to December 1900: Registration of marriage of Leonard Darwin; in Kensington (Volume 1a, Page 221)
• October to December 1900: Registration of marriage of Charlotte Mildred Langton; in Kensington (Volume 1a, Page 221)

From MyHeritage: Leonard Darwin: 1939 Register of England & Wales (transcription only)

29 September 1939 Census for residents of Cripps Corner, Goat Crossroad, Forest Row, East Sussex RH18 5JQ 51.068566, -0.003840, England

• Leonard Darwin, head, married, male, aged 89, born Tuesday, 15 January 1850; Occupation: Major, Retired
• Charlotte M Darwin, wife (implied), married, female, aged 71, born Saturday, 7 March 1868; Occupation: Private Means
• Ann E Lee, single, female, aged 62, born Wednesday, 11 April 1877; Occupation: Domestic Servant
• Thomas C Pitt, married, male, aged 47, born Sunday, 24 January 1892; Occupation: Gardener
• Bertha E Pitt, married, female, aged 44, born Sunday, 3 March 1895; Occupation: Unpaid Domestic Duties
• Frederick R Pitt, single, male, aged 14, born Sunday, 22 March 1925; Occupation: Cow boy
• Thomas A Pitt, single, male, aged 12, born Monday, 12 December 1927; Occupation: At School
• Gordon W Price, single, male, aged 16, born Thursday, 14 June 1923; Occupation: At School

From FreeBMD: Registration of death of Leonard Darwin in 1943

January to March 1943: Registration of death of Leonard Darwin; aged 93 [born about 1850]; in Uckfield, Sussex (Volume 2b, Page 251)

From British Newspaper Archive: Birmingham Mail Saturday, 27 March 1943 Page 4 Death of Charles Darwin's son

The death took place yesterday Friday, 26 March 1943, at the age of 93 of Major Leonard Darwin, fourth and last surviving son of Charles Darwin and Unionist M.P. for Lichfield from 1892 to 1895.

Major Darwin, who was eight years of age when his father made his famous "communication" to the Linnean Society on evolution, joined the Royal Engineers in 1871 and retired in 1890. He obtained leave from the Army to accompany several scientific expeditions, including the two which investigated the transit of Venus.

He was president of the Royal Geographical Society 1908-1911. In the latter year he founded the Eugenics Education Society for the study of means of improving the health and social conditions of the human race. Much initial criticism was eventually overcome and many of the reforms he advocated have long since been adopted.

From British Newspaper Archive: Grimsby Daily Telegraph Saturday, 27 March 1943 Page 1 Charles Darwin's last son

Major Leonard Darwin, the fourth and last surviving son of Charles Darwin, died yesterday, Friday, 26 March 1943, at Cripps Corner, Forest Row, Sussex, aged 93. Major Darwin was eight years of age when his father made his famous "communication" to the Linnean Society on evolution.

Major Darwin joined the Royal Engineers in 1871 and retired in 1890. He obtained leave from the to accompany several scientific expeditions, including the two which investigated the transit of Venus. He was President of the Royal Geographical Society 1908-1911.

From findagrave: Major Leonard Darwin (1850-1943)

• Name: Major Leonard Darwin (Veteran)
• Born: Tuesday, 15 January 1850, Downe, Greater London, England
• Died: Friday, 26 March 1943 (aged 93), Forest Row, Wealden, East Sussex, England
• Buried: [Forest Row Cemetery, Priory Road, Forest Row, East Sussex RH18 5HF 51.09656, 0.02998]
• About:

Leonard Darwin, the fourth and last surviving son of Charles Darwin and Emma Wedgwood, was born at Down House, Downe, Kent on Tuesday, 15 January 1850 and died in London on Friday, 26 March 1943. He entered the Royal Military Academy at Woolwich in 1868, and came second on the examination list, to his father's great joy. He served in the Royal Engineers, rising to the rank of major by 1890, and on scientific expeditions to photograph the transit of Venus. He taught at the School of Military Engineering at Chatham from 1877–82, and served in the intelligence division of the Ministry of War from 1895–90. He entered parliament in 1892 as Liberal-Unionist MP for Lichfield, holding the seat until 1895, during which time he began a serious study of economics. From 1908–11 he was president of the Royal Geographical Society. The dates of his respective marriages were: i.) Elizabeth on Tuesday, 11 July 1882;. ii) Charlotte Mildred: Thursday, 29 November 1900.

Leonard Darwin married Elizabeth Frances Fraser on Tuesday, 11 July 1882, but she died on Thursday, 13 January 1898 and was buried in Putney, London. On Thursday, 29 November 1900 he remarried, to his first cousin Charlotte Mildred Massingberd (1868–1940), the daughter of Edmund Langton (1841–1875) and granddaughter of Rev. Charles Langton and his wife Charlotte Wedgwood, the sister of Leonard Darwin's mother Emma. Their shared ancestor was Josiah Wedgwood II. Charlotte Mildred Massingberd's paternal grandfather, Charles Langton (1801–1886), married Charles Darwin's sister Emily Catherine Darwin, after Charlotte Wedgwood's death. Since Charles Darwin and Emma Wedgwood were cousins, Charlotte Mildred Massingberd was also a second cousin on his father's side. Leonard Darwin had no children from either marriage.