in Paris, boarding with a French family, so that in the two years of his stay he learnt the language well. On his return to England he went to a school at Norwood, and was then for two years under Richard Valpy [q. v.] at Reading. In his seventeenth year he joined University College, London, where he was attracted to science and chemistry. At the age of eighteen he entered his father's office, but though most conscientious in his attention to business, he devoted every spare moment to science, working till late in the night ; this habit, and living too sparingly so that he might spend more on books and instruments for his studies, probably did harm to his constitution, for though he lived to be old he was far from a healthy man.
Gradually Prestwich's interests concentrated on geology, and he began to study the coalfield of Coalbrookdale in Shropshire, which he described in two papers read before the Geological Society of London. The second of them at once established his reputation as a geologist. While in London he settled down to that close study, first of the Eocene and then of the Pliocene deposits, on which were founded his most important contributions to science.
His parents removed to Devonshire Street, Portland Place, in 1840, and in 1842, at a rather anxious crisis, the father ceded his place in the firm to the son, who then lived at the offices in Mark Lane. To his study of the tertiaries he had added that of water supply, and in 1851 published an excellent volume on the water-bearing strata round London. In the same year came the first of a series of most valuable papers on the Eocene strata of England and their continental equivalents, but the series did not close till 1888. He also closely studied the Pliocene deposits of the eastern counties, especially during the decade commencing with 1845, but the three papers which were the result were not published till 1871 ; though containing less new matter than those on the Eocene, they are models of exhaustive work. In one the iron sands on the North Downs, which at Lenham contain ill-preserved fossils, were classed as lower Crag. This identification was afterwards contested, but further investigation has confirmed Prestwich's view.
Late in the fifties he began to work at the antiquity of man, co-operating first in the exploration of Brixham cave, and then, in the spring of 1859, visiting the Somme valley in company with (Sir) John Evans, to examine into M. de Perthes's evidence for the existence of man when the gravels with remains of the mammoth were formed.
The results were embodied in a paper read to the Royal Society in May 1859, showing that, though M. de Perthes had been occasionally imposed upon, the main facts were indisputable. Then came the news that a human jawbone, supposed to be contemporary, had been found in the gravel at Moulin Quignon, Abbeville. Prestwich went with some English experts in 1863 to examine the specimen, and afterwards attended a conference on the subject at Paris, when they maintained the jaw to be much more recent than the gravel in which it had indubitably been found. The questions thus opened up engaged Prestwich's attention to the last, some of his latest papers being on certain flints found by Mr. B. Harrison and others on the North Downs, sometimes as much as 600 feet above sea level. Prestwich regarded them as bearing the marks of human workmanship, but some good judges maintain the fractures to be natural.
In 1864 he was placed on the Water Commission, and in 1866 was appointed to the Royal Coal Commission, on each of which he took a very active part, making most valuable contributions to their reports. As his health was suffering from such continuous strain, he determined to have a breathing place in the country, so he began to build near Shoreham, Kent, in 1864, Darent Hulme, a quaintly ornamented and very attractive house, in the garden of which he found a lifelong pleasure. But the loss at the end of 1866 of his sister Civil, who had been his devoted companion for the last ten years, overshadowed its completion.
February 1870 was marked by two important events: he became president of the Geological Society, of which he had already been secretary and treasurer, and a few days afterwards married Grace Anne M'Call, daughter of James Milne of Findhorn, and niece of Hugh Falconer [q. v.] In 1872 he found himself able to retire from business, and thus to indulge the desire of his life, and devote his whole time to scientific studies. But in June 1874, on the death of John Phillips (1800-1874) [q. v.], he was offered the chair of geology at Oxford, which after some hesitation he accepted. It was late in life to begin to teach, and Prestwich was not naturally a facile speaker or lecturer, but he threw himself vigorously into his new duties and the cause of scientific education in the university. Not the least of his services to it and the city was applying his special knowledge to obtain a better water supply. He received the degree of M.A. on 11 Nov. 1874, and was admitted a
