Harry E. Wood, astronomer, obtained a first class honours degree in physics at Owens College, University of Manchester, followed by the degree Master of Science (MSc) in physics. For some time he lectured in the university's Department of Physics and worked on interference phenomena of light. In 1905 he successfully applied for the post of chief assistant at the Meteorological Observatory of the Transvaal Colony in Johannesburg (which soon became the Transvaal Observatory, and from 1912 the Union observatory), under its director, R.T.A. Innes*. Before leaving England he received intensive training in meteorology and weather forecasting at the Meteorological Office in London and at the National Physical Laboratory at Kew (near London). He assumed duty in Johannesburg on 1 January 1906.
In July that year Wood started providing the first 24 hour weather forecasts in South Africa, which were distributed to telegraph offices throughout the Transvaal. However, Innes soon established astronomical work at the observatory and meteorological work was moved to the Meteorological Office in Pretoria in 1912. Early in 1909, while on leave in England, Wood was involved in negotiations with Mr John Franklin-Adams* relating to his gift of a star camera to the observatory. He acquired a sound knowledge of the instrument and for the rest of his career his observational work in astronomy was carried out mainly with the Franklin-Adams star camera. At first he used it to complete the Franklin-Adams star charts, and later for the Union Observatory star charts. With its large field of view and good light collecting ability the instrument was suitable also for Wood's other work - the discovery and observation of minor planets, comets and variable stars - while its short focal length presented no drawback. After it had been installed at the observatory in 1910 he used it to obtain 50 excellent photographs of Halley's Comet - probably the best photographs obtained anywhere during that return. He was a careful and painstaking oberver and for many years was one of only a few observers of minor planets (asteroids) in the southern hemisphere. Between 1911 and 1932 he personally discovered eleven new ones, which were named Transvaalia (1911), Pretoria (1912), Mancunia (1912), Franklina (1922), Pafuri (1924), Van den Bos (1926), Jackson (1926), McGlassen (1928), Pongola (1928), Reunerta (1928), and Dysonia (1932). Many more were discovered by other members of the observatory's staff.
For some time Wood was responsible for seismological observations at the observatory. His results were published in two papers, "The Witwatersrand earth tremors" (Journal of the Chemical, Metallurgical and Mining Society of South Africa, 1913/4) and "On the occurrence of earthquakes in South Africa" (Bulletin of the Seismological Society of America, 1913). In 1914 he travelled to Barotseland (in south-eastern Zambia) to make observations in connection with the magnetic survey of southern Africa, initiated by Professor J.C. Beattie* of the South African College, Cape Town. From April 1916, during World War I (1914-1918), he served in East Africa, but was invalided out in February 1917, suffering from malaria. The diseases continued to affect him for most of his life.
Most of Wood's work was published in the circulars of the Union Observatory. He also published papers and more popular articles on astronomy, meteorology and related topics in several other journals, for example "Measurement of the intensity of solar radiation" (Report of the South African Association for the Advancement of Science, 1909); "Snow storms in the Transvaal" (Ibid, 1909); "Notes on Halley's Comet" (Ibid, 1910); "Hail storms" (Transvaal Agricultural Journal, 1908/9); "What is the maximum temperature of a day?" (Meteorological Magazine, 1907); "Recent progress in astronomy" (South African Journal of Science, 1920); "The history of the Union Observatory" (Ibid, 1926); and "Astronomical relics at Touws River, C.P." (Ibid, 1937).
Wood was an active and respected member of many local and overseas scientific societies. He was elected a Fellow of both the Royal Meteorological Society and the Royal Astronomical Society (the latter in 1909), and became a member of the Astronomische Gesellschaft in 1913. By 1917 he was a member of the Royal Society of South Africa and was elected one of its Fellows in 1930. In 1906 he became a member of the South African Association for the Advancement of Science, serving as honorary general secretary for many years, as president of Section A (which included astronomy) in 1920, and as president of the association in 1930. He was an honorary vice-president of the Cape Astronomical Association (founded in 1910) and computed orbits for all the comets discovered by the association's Comet Section. Early in 1918 he became a foundation member of the Johannesburg Astronomical Association and during March to September that year presented a series of talks for beginners. In July 1922 the two associations amalgamated to form the Astronomical Society of South Africa. Wood served on its council for the first year, was the editor of its Journal from 1922 to 1925, and was elected president of the society for 1929-1930. Thereafter he served on the council until 1935 and contributed further articles to the Journal. In 1929 he was also a member of the South African National Committee in Astronomy and served on the executive committee that arranged the South African meeting of the British Association for the Advancement of Science that year. He became a foundation member of the South African Geographical Society in 1917, served on its first council, and contributed the first scientific article to its South African Geographical Journal (1917) on "The motion of the earth". His later contributions to this journal were "The climate of South Africa" (1918) and "Notes on the climate of the Transvaal" (1920). He was president of the society in 1933. In 1912 he was an examiner in meteorology for the BSc (Agriculture) degree of the University of the Cape of Good Hope.
In 1928 Wood succeeded Innes as director of the Union Observatory, while W.H. van den Bos became his chief assistant. One of his first tasks as director was to organise co-operation with the Lamont Hussey Observatory in Bloemfontein on the observations of double stars carried out at both institutions.
As a keen naturalist Wood cultivated stapelias and formed a collection of reptiles in jars while at the observatory. After his retirement in February 1941 he settled on a farm near Mortimer in the Eastern Cape, where he died five years later after a heart attack. He was a shy and reserved person, quick to be offended, but with a dry sense of humour. On 19 February 1909 he married Mary E. Greengrass, but they had no children. She was a fellow student from his Manchester days and assisted him in many of his tasks. In 1937 the University of the Witwatersrand conferred an honorary Doctor of Science (DSc) degree on him.