190. "Enquiries on the Causes of the Colour of the Water of the Rhine" (prose), March, no ms; printed Works 1:191–92.
	Along with “Facts and Considerations,” listed as no. 1 in R. H. Shepherd, Bibliography of Ruskin . . . (from 1834 to 1879), pp. 1–2; R. H. Shepherd, Bibliography of Ruskin . . . (from 1834 to 1881), p. 1. Hence these two prose pieces considered as earliest publications.
	Ruskin's first paper for Loudon's Magazine of Natural History (vol. vii, no. 41 [September 1834], pp. 438–39) was started by March, along with no. 191, when he refers to them in no. 189. In the first issue, Loudon announces the spirit in which Ruskin would have contributed his first published prose works.  Like many of the fancy literary annuals in which Ruskin published some of his early verse, the magazine drew "voluntary contributions" from its readers. "Every reader" was invited "to communicate . . . observations which, at first sight, may appear trivial, [but which] are often truly valuable when viewed in reference to general conclusions . . . [and which] may be furnished by persons wholly unacquainted with natural history as a science."  The magazine also undertook to educate amateurs with introductory papers on various fields of natural history (The Magazine of Natural History, ed. J. C. Loudon [London: Longman et al.], vol. 3 [1830], p. iii; and vol. 1 [1829], pp. 8–9).