24 September 1822|
Frankfurt am Main
|Died||5 December 1884
|Known for||Royal Agricultural Society of England|
Justus von Liebig
Gerardus Johannes Mulder
James Finlay Weir Johnston
Augustus Voelcker F.R.S. (24 September 1822 – 5 December 1884), full name John Christopher Augustus Voelcker, was a Royal Agricultural Society of England chemist. Voelcker was known for his methodical and precise analytical practices as applied to agricultural chemistry.
After working as a pharmacist's assistant in Frankfurt am Main until 1842, then in a similar capacity in Schaffhausen until 1844, Voelcker entered University of Göttingen where he studied chemistry under professor Friedrich Wöhler. He also attended University of Giessen, where the German chemist Justus von Liebig lectured on agricultural chemistry. He went to Utrecht in 1846 to work as assistant to professor Gerardus Johannes Mulder where Voelcker studied the chemistry of animal and vegetable production. In 1847 he went to Edinburgh as assistant to James Finlay Weir Johnston, the Highland and Agricultural Society of Scotland's chemist at the time. Whilst in Edinburgh, he lectured at Durham University and also became friends with the chemist George Wilson. From 1849, as the first professor of chemistry at the Royal Agricultural College, Cirencester, Voelcker lectured on such topics as sewage.
Voelcker was recruited as consultant chemist to the Royal Bath and West of England Society by Sir Thomas Dyke Acland, 11th Baronet in about 1849. He was appointed consultant chemist to the Bath Royal Literary and Scientific Institution in 1855, a post he held until 1863, although he continued to maintain connections with the society. Voelcker contributed to the society's journal and lectured throughout the area. He was well aware of agricultural economics, for, as he said
any good analytical chemist can ascertain the exact amount of the different constituents of the manure, and, knowing the market price at which they can be obtained separately, he is enabled to calculate with tolerable accuracy its commercial value
He set up a private consulting practice in London in 1863; he provided advice in many fields including sewage, water and gas supply, river pollution, and agricultural holdings. For example, by using the cost of ammonia as nine pence per pound, and the cost of phosphates as two pence per pound, an 1885 book reported Voelcker as calculating the annual value of excrement per adult as nine shillings (worth 44 pound sterling in 2017). He was elected chairman of the London Farmers Club in 1875.
- Several papers in German and Dutch scientific journals (1844–1846)
Works taken from 
- Voelcker, A (April 1850). "Analysis of the Anthracite of the Calton Hill, Edinburgh". Edinburgh New Philosophical Journal. Read before the Royal Society of Edinburgh, 4 March 1850
- Voelcker, Augustus (March 1850). "On the Watery Secretion of the Leaves and Stems of the Ice-plant (Mesembryanthemum crystallinum, L.)". Annals and Magazine of Natural History. Read before the Botanical Society of Edinburgh, 10 January 1850
- Voelcker (March 1851). "The Effects of Burnt Clay as a Manure". Journal of Agriculture, and transactions of the Highland and Agricultural Society of Scotland.
- Voelcker, Augustus (January 1853). "On the comparative value of white Scottish and black English oats; and on the composition of rice-meal". Journal of Agriculture, and Transactions of the Highland and Agricultural Society of Scotland.
- Voelcker, Augustus (July 1854). "On the composition of green rye and rape". Transactions of the Highland and Agricultural Society of Scotland.
- Voelcker, Augustus (January 1854). "On the composition of the parsnip and white Belgian carrot". Journal of the Royal Agricultural Society of England. XIII (2).
- Voelcker, Augustus (1855). "On the comparative value of different artificial manures for raising a crop of swedes". Journal of the Royal Agricultural Society of England. XVI (1).
- Voelcker, Augustus (1855). "On the agricultural and commercial value of some artificial manures, and on their adulteration". The Bath and West of England agricultural journal. III.
- Voelcker, Augustus (1856). "On the chemistry of food". The Bath and West of England agricultural journal. IV.
- Voelcker, Augustus (1856). "Four lectures: On the composition of farmyard manure, and the changes which it undergoes on keeping under different circumstances". Journal of the Royal Agricultural Society of England. XVII (1).
- Voelcker, Augustus (1857). "Four lectures: Farmyard manure, Artificial manures, Barren and fertile soils, Oil-cakes". Agricultural chemistry.
- Voelcker, Augustus (1857). "On Farmyard manure, the drainings of dung-heaps, and the absorbing properties of soils". Journal of the Royal Agricultural Society of England. XVIII (1).
- Voelcker, Augustus (1858). "On the use of lime, marl, and shell-sand in agriculture". The Bath and West of England Agricultural journal. VI.
- "Augustus Voelcker". Oxford Dictionary of National Biography (online ed.). Oxford University Press. doi:10.1093/ref:odnb/28345. (Subscription or UK public library membership required.)
- Clarke, Ernest (1899). "Voelcker, John Christopher Augustus". In Lee, Sidney. Dictionary of National Biography. 58. London: Smith, Elder & Co.
- Williams, W J. "Scientific Societies and Institutions in Bath". Bath Royal Literary & Scientific Institution. Archived from the original on February 17, 2012. Retrieved 4 March 2016.
- Voelcker, Augustus (1862). Lecture on Town Sewage. Royal Agricultural Society.
- Hudson, Kenneth. "The Bath & West: A short History". The Royal Bath & West of England Society. Archived from the original on 20 June 2010. Retrieved 20 July 2010.
- Using RPI as described in Choosing the Best Indicator to Measure Relative Worth
- Denton, John Bailey (1885). Sewage Disposal: Ten Years' (Now Fourteen Years) in Works of Intermittent Downward Filtration (PDF) (2 ed.). E and F N Spon. pp. 93–94. Retrieved 18 July 2010.
- "Obituaries: A. F. Voelcker" (PDF). British Medical Journal. 1 (4459): 969. 22 June 1946. PMC .
- Voelker, Augustus (1850–1862). Agricultural pamphlets. Library of the University of California. pp. 1–44. Retrieved 8 July 2016.