Blackwall, John (DNB00)
BLACKWALL, JOHN (1790–1881), zoologist, was born at Manchester 20 Jan. 1790. After some years' partnership with his father, an importer of Irish linen, he retired in 1833 to North Wales, settling ultimately at Llanrwst. As early as 1821 he published, in Thomson's 'Annals of Philosophy,' observations on diurnal mean temperature, and in 1822 some notes by him on migratory birds appeared in the 'Memoirs of the Manchester Philosophical Society.' This was followed by observations on the notes of birds. Fifteen of his first twenty-five papers were ornithological. Being attracted to the study of spiders and their webs, he was surprised to find scarcely any available authorities, and this determined his choice of a principal lifework. His first paper on spiders appeared in 1827 in the 'Transactions of the Linnean Society,'. on the means by which gossamer spiders effect their aerial excursions. In 1830 he published, in the 'Zoological Journal,' a paper on the manner m which the geometric spiders construct their nets. His papers were collected in 'Researches in Zoology,' 1834; the second edition, 1873, was not brought up to date. Blackwall pursued the study of the spiders of his own neighbourhood and their habits with extreme painstaking, almost wholly unaided by any British or foreign worker. His great work, ' A History of the Spiders of "Great Britain and Ireland,' 1861-4, published by the Ray Society, was unfortunately in the hands of the society ten years before its publication. It is full of minute detail, giving an almost photographic picture of the object. Nearly all his work was done without any aid but that of a pocket lens. Some of his type-specimens are lost, owing to their having been kept indiscriminately with others. His writing for the press was most remarkably clear, and scarcely a single correction was needed in his proof-sheets. He died 11 May 1881.
[Obit, notice in the Entomologist, xiv. 145-50, by Rev. O. Pickard-Cambridge; see also xiv. 190, and Entomologist's Monthly Mag. xviii. 45.]