by Ernest Clarke

“ He left Göttingen to take up the post of principal assistant to Professor Gerrit Jan Mulder at Utrecht, aiding him in preparing his ‘Chemische Untersuchungen’ (Frankfort, 1852, 8vo) . Mulder devoted much attention to the study of physiological chemistry, especially in its relation to vegetable and animal production. Though Voelcker's stay at Utrecht was short, his work there fixed the ultimate bent of his researches. In February 1847 he went to Edinburgh to be assistant to James Finlay Weir Johnston [q. v.] , then chemist to the Agricultural Chemistry Association of Scotland. ”

“ Ill-health during childhood postponed the commencement of his education until he was twelve years old, but by persevering energy he was able at the age of sixteen to earn his own living as a pharmacist's assistant at Frankfort. After a four years' course in that capacity he went in 1842 as manager of a similar business at Schaffhausen. In 1844 he entered the university of Göttingen, where he studied chemistry under Professor Wöhler. During his college career he also attended Justus von Liebig's lectures on agricultural chemistry at Giessen. ”

“ Maria Josepha Holroyd, daughter of Lord Sheffield, speaks of him in July 1795 as a sensible well-informed man, who had visited several countries and profited by his travels (Girlhood of Maria Josepha Holroyd, 1896, p. 326) . ”

“ Another invention, which, according to his editor, brought him into ‘yet more vagations or wanderings,’ was a winnowing machine which he perfected in 1772. A third invention was ‘a machine for taking off friction.’
In 1784 he was living in Sloane Square. ”

“ By carrying out practical field experiments, in combination with scientific work in the laboratory, he was able to put to the test matters of agricultural practice and to study their scientific import. ”

“ VARLO or VARLEY, CHARLES (1725?–1795?) , agriculturist, was born in Yorkshire about 1725. He visited Ireland in his twenty-first year, spending some time with Edward Synge [q. v.] , bishop of Elphin. 'At that period,' writes in 1796 the anonymous editor of Varlo's 'Floating Ideas,' 'being fifty years back, farming in Ireland was in its infancy; but flax-farming was yet less known, neither had the linen board been long instituted ”