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Delos  Arnold

Delos Arnold was born in New Berlin, Chenango County, New York on July 21, 1830, the son of Rebecca Colburn and Andrew Arnold (1807-1856), a tanner and trader. In 1841 the family moved to Chautauqua County, New York where Delos attended Fredonia Academy; he later graduated from the Albany Law School in 1853. Upon graduation he moved to Marshalltown, Iowa where he practiced law for the next 33 years. For several years he was treasurer and district attorney for Marshall County. Arnold married Hannah R. Mercer in 1855 and together they had six children including Ralph Arnold, who was also a geologist and mineral collector.

The discovery of crinoid fossils in nearby LeGrand, Iowa, led Arnold to take up the study of fossils in 1860, and he assembled an extensive private collection. President Lincoln appointed him in 1862 as U.S. Assessor for Internal Revenue for the sixth Iowa district, a position he held for four years. He then served for 12 year as a member of the Iowa State Legislature. In 1861 he entered the real estate and money-lending business, and in 1870 took over a furniture store.

In the summer of 1872, Arnold and several of his friends took an extended tour through Colorado and the Rocky Mountains, collecting minerals along the way. In 1873 he visited the World's Fair in Vienna, Austria, and traveled throughout Europe. In 1875 he was elected to the Iowa State Senate for a four-year term. By 1877 he was also engaged in the coal business and was a part-owner of the Iowa Railroad, Coal, and Manufacturing Company.

In 1886 Arnold and his family moved to Pasadena, California. There he served as President of the Pasadena Academy of Sciences in 1890. He presented his extensive collection of minerals, fossils, shells, corals and ethnographic materials to Stanford University in 1908. Most of the mineral specimens were collected in Colorado in the 1870s and in Arizona in the 1880s. He died August 31, 1909 in Pasadena.

ANON. (1908) The Delos Arnold collections of natural history specimens. Science, 28 (725), 717-718.
ANON. (1878) United States Biographical Dictionary, Iowa Volume.
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