# Dictionary of National Biography, 1912 supplement/Dallinger, William Henry

​DALLINGER, WILLIAM HENRY (1842–1909), Wesleyan minister and biologist, born in Devonport on 5 July 1842, was son of Joseph Stephen Dallinger, artist and engraver. He was educated privately. In boyhood he showed a bent towards natural science, but his religious instinct led him to qualify for the Wesleyan ministry in 1861. After serving Wesleyan churches in Faversham, Cardiff, and Bristol, he passed to Liverpool, where he remained twelve years (1868-80). There in 1870 he began microscopic researches into minute septic organisms, which he pursued for ten years. In 1880 he was appointed governor and president of Wesley College, Sheffield, and had held the post for eight years, when the Wesleyan conference, recognising his scientific attainments, allowed him to retire from the position whilst retaining the status and privilege of a Wesleyan minister without pastoral charge. In addition to his work as minister and governor, Dallinger was a uccessful public lecturer on microscopical subjects. For thirty years he lectured for the Gilchrist Educational Trust.
Dallinger's contributions to science are of two kinds his classical investigations into the life-history of certain micro-organisms, and his improvements in microscopical technique. The organisms he worked at in collaboration with Dr. John James Drysdale of Liverpool were 'flagellates' or 'monads,' about the life-history of which little was known. Dallinger showed not only unwearied patience and application but a mastery of manipulation. By using a binocular instrument an individual monad was kept under observation first by one and then by the other of the two students for a considerable time; on one occasion for thirty-two hours. By such means the transformations of these obscure animals were established. In addition to these important investigations, Dallinger and his colleague contributed valuable evidence in regard to the then controverted question of abiogenesis. They were able to show that by acclimatising these monads to an increasingly high temperature, they acquired a power of living freely in a temperature far above the normal, and one which is lethal to unacclimatised specimens. Further, they proved that though the temperature of boiling water was fatal to all such monads in an active state, yet that their spores were extraordinarily resistant, enduring a temperature of 268° in water and 300° or more in a dry state. These discoveries showed that the ordinary precautions (such as boiling) by which organic solutions are sought to be sterilised are insufficient, and they also explain the origin of life in experiments where spontaneous generation had been supposed to occur.
As an expert microscopist, Dallinger enjoyed the highest reputation. He occupied the post of president of the Royal Microscopical Society four times (1884–7) and that of the Quekett Club (1890–2). He was elected F.R.S. in 1880; hon. LL.D. of Toronto in 1884; D.Sc. of Dublin in 1892, and D.C.L. of Durham in 1896. In 1879 he delivered the Rede lecture at Cambridge on 'The Origin of Life,' illustrated by the life-histories of the least and lowest organisms in nature. His chief papers are published in the 'Monthly Microscopical Journal' (1873–6). He rendered students a great service by editing and rewriting Carpenter's classical book, 'The Microscope and its Revelations' (1890; new edit. 1901). He was also author of a theologico-scientific work, 'The Creator and what we may know of the Method of Creation' (1887). A good portrait of him was published in the 'Journal of the Royal Microscopical Society' for 1909.
[Nature, 1909, lxxxii. 71; Proc. Roy. Soc. 1910, lxxxii. B. iv; personal knowledge.]
F. W. G.