Editing Camel case (section)

=== Chemical formulas ===
The first systematic and widespread use of medial capitals for technical purposes was the notation for chemical formulas invented by the Swedish chemist [[Jöns Jakob Berzelius|Jacob Berzelius]] in 1813. To replace the multitude of naming and symbol conventions used by chemists until that time, he proposed to indicate each chemical element by a symbol of one or two letters, the first one being capitalized. The capitalization allowed formulas like "[[sodium chloride|NaCl]]" to be written without spaces and still be parsed without ambiguity.<ref>[[Jöns Jacob Berzelius]] (1813). ''Essay on the Cause of Chemical Proportions and on Some Circumstances Relating to Them: Together with a Short and Easy Method of Expressing Them''. ''[[Annals of Philosophy]]'' 2, 443-454, 3, 51-52; (1814) 93-106, 244-255, 353-364.</ref><ref>[[Henry M. Leicester]] & Herbert S. Klickstein, eds. 1952, ''A Source Book in Chemistry, 1400-1900'' (Cambridge, MA: Harvard)</ref>

Berzelius' system continues to be used, augmented with three-letter symbols such as "[[ununennium|Uue]]" for unconfirmed or unknown elements and abbreviations for some common substituents (especially in the field of organic chemistry, for instance "[[Ethyl group|Et]]" for "ethyl-"). This has been further extended to describe the [[amino acid]] sequences of [[protein]]s and other similar domains.