Died: 17 January 1911 in Grayshott House, Haslemere, Surrey, England

An explorer and anthropologist, Francis Galton is known for his pioneering studies of human intelligence. He devoted the latter part of his life to eugenics, i.e. improving the physical and mental makeup of the human species by selected parenthood.

Galton's parents, both from important Quaker families, might have served as excellent examples of his ideas on hereditary genius. His mother, Frances Anne Violetta Darwin, was the daughter of the physician Erasmus Darwin, the author of Zoonomia or the Laws of Organic Life, in which he set out his ideas of evolution. Charles Darwin was also a grandson of Erasmus Darwin. Galton's father, Samuel Tertius Galton, was a banker from a family which contained many rich bankers and gunsmiths. Francis was youngest of his parents seven children having three older brothers and three older sisters.

Francis attended a number of small schools in the Birmingham area before entering King Edward's School in Birmingham in 1836. He spent two years at this school but did not find the emphasis on classics and religion to his liking. Since his parents had decided that he should follow a medical career, he was an apprentice to several different medical men in Birmingham for around a year. Following this he went to London where he studied medicine at King's College for one year. Then, in 1840, he made a quick tour of the Continent visiting Giessen, Vienna, Constanza, Constantinople, Smyrna, and Athens. It was at this stage that, in his own words, (see [6]):-

... a passion for travel seized me as if I had been a migratory bird.

On his return to England Galton entered Trinity College, Cambridge, to study medicine in the autumn of 1840. He quickly changed his studies to mathematics, studying with Hopkins, the best Cambridge mathematics tutor, but he became ill during his third year and was unable to complete his degree. Much of his problems at this time came from the fact that his father was seriously ill, and that was undoubtedly a major factor in his failing to be able to complete the Mathematical Tripos. His intention at this time was to return to a medical career, and indeed he went back to London where he took up his medical studies again. However, after his father died in 1844, he found himself well off with [6]:-

... a sufficient fortune to make me independent of the medical profession.

No longer needing to think in terms of a career since he was financially secure, Galton decided to follow his passion for travel and made a trip with friends up the Nile to Khartoum. There was much interest in the Nile at this time with a great deal of speculation as to its source. In fact the Nile is two rivers, the White Nile and the Blue Nile, which join at Khartoum and flow together to the sea. (In fact the source of the Nile was not discovered to be Lake Victoria until 1858.) Galton also visited the Holy Land and Syria before deciding that he would devote himself to sport, which he did for five years from 1845 at 1850.

Deciding that sport did not suit him, Galton began to plan more ambitious travels. He consulted the Royal Geographical Society before deciding on a trip to south west Africa. David Livingstone had sent a report to a meeting of the Royal Geographical Society on finding Ngami Lake in 1849 which is located in the north west of present day Botswana. The existence of the lake, to the north of the waterless Kalahari Desert, was already known to Europeans but Livingstone was the first European to see it. Galton aimed to find a passage to the lake from the south west, and with this plan in mind his expedition landed in Walvis Bay (in present day Namibia). East of Walvis Bay was the region known as Damaraland, which had been first visited by Europeans in 1791. In fact Walvis Bay to Ngami Lake is around 550 miles and, despite two attempts to reach the lake, Galton's party failed in both attempts. It was a very worthwhile expedition, however, and they learnt much of this region which had been little explored by Europeans. When Galton returned to England he published an account of his journeys in Tropical South Africa (1953). He was elected a fellow of the Royal Geographical Society in 1853 as a result of his explorations and, three years later, he was elected a fellow of the Royal Society.

On 1 August 1853 Galton married Louisa Jane Butler, the daughter of the dean of Peterborough who had previously been headmaster of Harrow School. He wrote another interesting book aimed at giving advice to explorers The art of travel but, although he continued to travel a great deal in Europe, he made no further explorations as a result of his health which never recovered from his African experience.

Perhaps it was the publication of Charles Darwin's Origin of the species in 1859 which marked a change in direction of Galton's interests. Galton was the cousin of Charles Darwin, so perhaps it was natural that he should be one of the first to be converted by the book. He became convinced that pre-eminence in various fields was due almost entirely to hereditary factors, something which was completely at odds with thinking at the time which basically believed that everyone was born with equal abilities. After reading Galton's book Hereditary Genius (1869) Charles Darwin wrote to him saying [6]:-

You have made a convert of an opponent in one sense for I have always maintained that, excepting fools, men did not differ much in intellect, only in zeal and hard work.

Galton opposed those who claimed intelligence or character were determined by environmental factors and defined "genius" as:-

... an ability that was exceptionally high and at the same time inborn.

He inquired into racial differences, something almost unacceptable today, and was one of the first to employ questionnaire and survey methods, which he used to investigate mental imagery in different groups of people.

Although weak in mathematics, despite studying the Mathematical Tripos for two years, his ideas strongly influenced the development of statistics particularly his proof that a normal mixture of normal distributions is itself normal. Another of his major findings was reversion. This was his formulation of regression and its link to the bivariate normal distribution. His work led him to the study of eugenics [3]:-

Galton may be described as the founder of the study of eugenics. His principal contributions to science consisted in his anthropological inquiries, especially into the laws of heredity, where the distinguishing feature of his work was the application of statistical methods. In 1869, in 'Hereditary Genius', he endeavoured to prove that genius is mainly a matter of ancestry, and he followed that up with many other books and papers on various aspects of the subject.

Let us examine Galton's contribution to statistics in a little more detail. In around 1875 he was experimenting with sweet-pea seeds. He used 100 seeds of each of seven different diameters and constructed a two-way plot of diameters of the original seeds against the diameters of the seeds of the next generation. He noticed that the median diameter of the offspring of the large seeds were less than that of their parents while the median diameter of the offspring of the small seeds were greater than that of their parents. Galton realised that the off-spring tended to revert towards the mean size. Certainly he did not understand at this stage that his findings would apply to any two-way plot, thinking rather than it was peculiar to the situation with which he was experimenting. At first he called the phenomena 'reversion', but later changed the name to 'regression'.

In 1884-85 the International Health Exhibition was held and in connection with this Galton set up a laboratory to measure human statistics. He collected data such as height, weight, and strength of a large number of people devising himself the apparatus used to make the measurements. This laboratory continued in existence after the International Health Exhibition closed and it was the forerunner of the Biometric Laboratory run by Karl Pearson at University College, London.

Galton now made further progress with the ideas he had already formed concerning regression. He made two-way plots of heights of parents and the heights of their adult children. He was able to draw the plots in such a way that the coefficient of regression became the slope of the regression line. In 1888 he also examined the size of two different organs from the same person and applied the methods he had been developing to study the degree of association of the sizes. He defined an index of correlation as a measure of the degree to which the two were related. However, when there are more than two measures which were correlated, he failed to understand the complexity of the mathematics involved.

In 1889 Galton published Natural inheritance in which presented as summary of the work he had done on correlation and regression. He gave a good account of the concepts which he had introduced as well as the techniques which he had discovered. Karl Pearson read Natural inheritance and it had a profound influence on his thinking:-

It was Galton who first freed me from the prejudice that sound mathematics could only be applied to natural phenomena under the category of causation. Here for the first time was a possibility - I will not say a certainty - of reaching knowledge as valid as physical knowledge was thought to be, in the field of living forms and above all in the field of human conduct.

Among the data which Galton collected in his laboratory were impressions of fingers. He was able to show that the fingerprint pattern remained constant as the person grew older, and he devised characteristics of the fingerprints which could be used as unique identifiers of the person based on grouping the patterns into arches, loops, and whorls. On the topic he published Finger prints (1893), Blurred finger prints (1893), and Finger print directory (1895). His identification system became the basis for the classification of Sir Edward R Henry, who later became chief commissioner of the London metropolitan police. The Galton-Henry system of fingerprint classification was published in June 1900, and began to be used at Scotland Yard in 1901 as an identifier on criminal records. It was soon used throughout the world in criminal investigations.

As well as being an indefatigable investigator of human intelligence, Galton made important contributions to the fields of meteorology, anthropometry, and physical anthropology. He published Meteorographica, or methods of mapping the weather in 1863. He created the term anticyclone and pointed out its importance in weather forecasting. Along with other important contributions made to meteorology, this led to him serving on the governing committee of the Meteorological Office.

Galton received many honours for his contributions, perhaps the most notable being that he was knighted in 1909 [3]:-

He was in his 89th year when the Prime Minister offered to submit his name to the King for a knighthood. With his usual modesty he accepted ...

He also received the Royal Medal from the Royal Society in 1876, the Darwin Medal of the same Society in 1902, and its Copley Medal in 1910. He was awarded the Huxley Medal from the Anthropological Institute in 1901 and the Darwin-Wallace Medal from the Linnean Society in 1908.

He played a major role in British science. In addition to the contributions mentioned above he was general secretary of the British Association from 1863 to 1867 and was sectional president on four occasions. He also served on the Kew committee of the Royal Society. His health began to limit the contributions he could make as he grew older [3]:-

1. N T Gridgeman, Biography in Dictionary of Scientific Biography (New York 1970-1990). 
   http://www.encyclopedia.com/doc/1G2-2830901572.html
2. Biography in Encyclopaedia Britannica. 
   http://www.britannica.com/eb/article-9035934/Sir-Francis-Galton

Books:

1. D W Forrest, Francis Galton : the life and work of a Victorian Genius (London, 1974).
2. F Galton, Memories of my life (London, 1908).
3. K Pearson, The Life, Letters, and Labours of Francis Galton (London, 1914-30).

Articles:

1. R E Fancher, Galton on examinations : an unpublished step in the invention of correlation, Isis 80 (303) (1989), 446-455.
2. P J FitzPatrick, Leading British statisticians of the nineteenth century, Journal of the American Statistical Association 55 (1960), 38-70.
3. P J FitzPatrick, Leading British statisticians of the nineteenth century, in M G Kendall and R L Plackett (eds.), Studies in the History of Statistics and Probability II (London, 1977), 180-212.
4. R W Morgan, Sir Francis Galton (1822-1910), in Some nineteenth century British scientists (Oxford, 1969), 65-95.
5. E S Pearson, Some reflections on continuity in the development of mathematical statistics 1890-94, Biometrika 54 (1967), 341-355.
6. S M Stigler, The History of Statistics. The Measurement of Uncertainty before 1900 (Cambridge, Mass.-London, 1986), 265-.
7. S M Stigler, Francis Galton's account of the invention of correlation, Statist. Sci. 4 (2) (1989), 73-79.