Australian Dictionary of Biography

Guillaume Daniel Delprat (1856-1937), engineer, metallurgist, and pioneer industrialist, was born on 1 September 1856 at Delft, Holland, son of Major General Felix Albert Theodore Delprat (1812-1888), sometime minister of war, and his wife Elisabeth Francina, née van Santen Kolff. The family moved to Amsterdam in 1865 where he attended a local high school. From 1873 to 1877 he served an engineering apprenticeship on the ill-fated Tay Bridge in Scotland—when he attended science and physics classes at Newport, learned differential and integral calculus from his father by post, and added Italian to his command of French, English and German. On his return to Holland he is said to have acted as assistant to J. van der Waals, professor of physics at the University of Amsterdam. On 4 September 1879 in Holland he married Henrietta Maria Wilhelmina Sophia Jas.

In 1879 Delprat began a mining career in Spain at the Tharsis Sulphur and Copper Mines. Three years later he switched to the Bede Metal Co., becoming general manager of its Spanish concerns at a salary of £700. Energetic and resourceful, he won much renown for his location and working of forgotten Roman silver mines. From 1891 for a time he was based in London where he became a Freemason. In February 1892 he published in Transactions of the American Institute of Mining Engineers an article, 'Extraction of ore from wide veins or masses', which first alerted Broken Hill Proprietary Co. Ltd to his potential. Though he continued to work for Bede's he also took up consulting engineering partnerships. By the mid-1890s he was a well-known mining authority as a result of the expansion of his work to Mexico and North America.

In June 1898 Delprat accepted an offer to become assistant general manager of B.H.P. On 3 September he arrived in Adelaide where he was met by the general manager (Sir) Alexander Stewart, whom he succeeded next year. Delprat's wife and five of their seven children arrived in January 1899 and, after a period in Broken Hill, settled in Adelaide from 1904 where they remained until moving to Melbourne in 1913. Delprat himself spent many of these years at Broken Hill. In 1904 he was naturalized.

In the early 1900s depressed prices and wasteful ore extraction methods limited profits. Delprat played an important part in the perfecting of a technique that came to be known as the [C.V.] Potter-Delprat flotation process; it revolutionized sulphide ore treatment and brought enormous profits from the metal content of millions of tons [tonnes] of formerly useless tailings. He received from B.H.P. £1000 for his patents and from January 1903 his salary was raised from £3000 to £4000. Delprat secured B.H.P.'s profitability through a switch of emphasis from silver-lead to zinc and sulphur, a detailed survey of ore reserves, the sinking of another shaft, and the addition of another mill, thereby more than doubling the output of sulphide ore. Perhaps his major contribution, however, was to foresee the exhaustion of the Broken Hill mine and to push for the removal of the company's smelters to Port Pirie and for the construction of its Iron Knob railways, in preparation for the exploitation of its ore resources there. The diversion of the company's interests from those of Broken Hill, was underlined both by Delprat's quitting the Mine Managers' Association presidency during the 1908-09 industrial dispute, and by the company's abrasive industrial relations during that dispute. His actions attracted the criticism of some of Broken Hill's other managers, notably W. S. Robinson who, in his memoirs, accused Delprat of sharp practice.

In 1911 Delprat, with the help of John Darling, persuaded B.H.P.'s board to consider establishing a steel-works utilizing the Iron Knob deposit. Delprat had visited Europe and America in 1907 to assess overseas developments. On six months leave from July 1911, he visited America, Britain and Europe to investigate their steel industries. His report was accepted by B.H.P.'s board, as was his suggestion to employ an American steel expert, David Baker, as manager. Delprat was prominent and effective in the complex negotiations with the Commonwealth and New South Wales governments which led to the signing of a contract on 24 September 1912 for the erection of the B.H.P. steelworks at Newcastle. The works were opened on 2 June 1915 by the governor-general, Sir Ronald Munro Ferguson, with whom Delprat forged a close relationship.

The establishment of the Newcastle works represented Delprat's crowning achievement. His vision, judgment and timing were vindicated not only by their opening in the early months of World War I, but also by his choice of American rather than the cheaper, but strategically vulnerable, German steel-making plant. His achievement was recognized officially in 1918 when he was appointed C.B.E. His only failure in connexion with the Newcastle works was the abandonment of his ship-building plans, in deference to Prime Minister Hughes's proposals for government enterprise.

During World War I Delprat was on the original sub-committee which established the Commonwealth Bureau of Science and Industry and on its advisory council. He was also on the defence Board for Construction of Aeroplanes and the Arsenal Construction Committee. In 1919 Delprat again made a working visit to America, Britain and Europe. In March 1921, after some of his decisions had been criticized by his heir apparent, Essington Lewis, and then overturned by the B.H.P. board, Delprat resigned as general manager, but continued as consultant engineer for two years at the same salary.

In a speech in 1920 Delprat denied being the initiator of the Australian steel industry. However he believed that the great wealth taken from Broken Hill had imposed upon B.H.P. a responsibility to reinvest at least a portion in Australia's future; and it was his suggestion to make that investment in steel. He had sought to avoid ancillary ventures to permit concentration on making as much high quality steel as possible; so he had encouraged B.H.P.'s biggest customers to settle near the Newcastle works. Baker had persuaded him to this policy, but it did not long survive Delprat's retirement—yet it laid the foundations of B.H.P.'s future dominance of Australian industry.

In retirement, with H. V. McKay and others, Delprat was a founder and tireless worker for the Single Purpose League which from 1922 to 1924 devoted itself to ending compulsory arbitration. He became chairman of Rylands Bros Ltd in 1921. Until 1928 he was an active council-member (and sometime president) of the Australasian Institute of Mining and Metallurgy which in 1935 awarded him a medal and life membership. He was also made a life member of the (Royal) Melbourne Hospital on whose board he had served for many years. In 1918 he had been admitted as an associate member of the Australian Chemical Institute; in 1920 he was elected fellow of the Royal Society for the Encouragement of Arts, Manufactures and Commerce, London; in 1935 he was elected to honorary membership of the American Institute of Mining and Metallurgical Engineers in recognition of his contribution to the development of the flotation process and his pioneering work in Australia's iron and steel industry. In the later 1920s he began to spend more time at his Healesville property and at wireless and sculpture; his bust of Braille won him the award of a silver medal by the French government in 1929.

Delprat made his last visit to Newcastle in September 1935. On 15 March 1937 he died in Melbourne after a short illness and was cremated. To his wife, who died on 5 December in the same year, and to his two sons and five daughters, one of whom married (Sir) Douglas Mawson, he left an estate valued for probate in Victoria at £53,005, at £5687 in New South Wales and at £900 in South Australia.