Abstract
Reports Second Report of the Committee, consisting of Prof. A. W. Williamson, Chairman, Profs. Sir H.E. Roscoe, Dewar, Frank-land, Crum-Brown, Odling, and Armstrong, Messrs. A. Vernon-Harcourt, J. Millar Thomson, V. H. Veley, F. Japp, H. Forster Morley, and H. B. Dixon (Secretary), appointed for the purpose of drawing up a Statement of the Varieties of “Chemkal Names” which have come into use, for indicating the causes which have led to their adoption, and for considering what can be done to bring about some Convergence of the Views on Chemical Nomenclature obtaining among English and Foreign Chemists.—The Report is somewhat lengthy, and includes some long tables of varieties of names for common chemical substances. It commences with historical notes on chemical nomenclature. No attempt was made until about 100 years ago to name chemical substances in a way which would indicate their composition; alchemistic or “culinary” names being given to substances in many cases. Macquer is credited with being the first to introduce generic names like vitriol and nitre to indicate sulphates and nitrates. The term salt was used to indicate almost any substance soluble in water and affecting the sense of taste, and in the eighteenth century acids, salts, and bases began to be distinguished. Rouelle was the first to define a salt from its chemical properties, and distinguish it from acids and bases (see Kopp's “History of Chemistry,” iii.). Bergmann and Guyton de Mouveau separately proposed systems of nomenclature, many terms of which are still in use. De Mouveau made the terminations of names of acids uniform, and the names of salts to indicate their composition from bases and acids. In 1787 Lavoisier, De Mouveau, Berthollet, and Fourcroy prepared a scheme of naming compounds which is practically that in common use now, introducing the terminations “ate” and “ic,” “ite” and “ous,” in acids and salts. But higher and lower oxides are not distinguished by generic names. Berzelius made a more elaborate classification of salts, and added some names. He distinguished the halogen compounds of hydrogen as hydracids, and distinguished clearly between “neutral,” “acid,” and “basic” salts. The views now held of acids, salts, and bases are practically those of Gerhardt and Laurent, who first recognised the part played by hydrogen in acids and salts. The Report then goes on to consider the tables, which give the number of times a substance has been distinguished by any particular name. Table I. deals with the names of oxides of carbon from 1755 t0 1882. By far the greater number of sources give the names carbonic oxide to CO and carbonic acid to CO2; systematic names like carbonous oxide and carbonic oxide only occurring two or three times, the terms carbonic oxide and carbonic anhydride or dioxide being next in frequency. In France and Germany the names oxide de carbon and acide carbonique, Kohlenoxyd and Kohlensäure have been much more frequently used. But in several instances the same names have been used in a different sense; the term carbonic oxide being sometimes used for CO2, sometimes for CO. In Table II. the prominence of this “diversity of names for the one thing,” and giving the same na ne to distinct substances, is more frequent. The use of numerical prefixes has also been very irregular; “thus, trisodic phosphate has been called ‘triphosphate of soda,’ ‘diphosphate of soda,’ and ‘sesquiphosphate of soda’; in all these cases the prefix is intended to indicate the number of molecules of soda to one molecule of phosphoric acid.” “In some of the older forms of nomenclature ambiguity was avoided by using the prefix ‘bi-’ to multiply the acid when in excess over the base, and ‘di-’ to multiply the base when in excess over the acid; thus, Na2O2SiO2, bisilicate of soda, 2Na2OSiO2, disilicate of soda.” The Report goes on to say that “the usefulness of any system of nomenclature depends on its permanence.” Curiously enough the tables show that where names have been adopted supposed to represent in some way the chemical constitution of bodies, they have not, as a rule, endured; the advance of knowledge necessitating a change of opinion, whilst names not expressing a chemical opinion as to constitution have endured. “As a rule, those names are to be preferred which have shown most vitality and have led to no ambiguity. Where there are two compounds composed of the same elements, the terminations ‘ous’ and ‘ic’ should be employed. The prefixes ‘proto’ and ‘deuto,’ introduced by Thomas Thomson, were intended to mark the compounds in a series, not the number of atoms in a molecule. Where retained this use only should be made of them.” Referring to change of name, instance is made of the oxides of carbon, the names of which have recently to some extent been transposed, the higher one being termed “carbonic oxide,” and the lower one, to which the term “carbonic oxide” has long been applied, has had a new name. The sensible conclusion of the Report is to retain names of substances which are in common use, rather than to change them for names indicating constitution, and which might be again found to require alteration in accordance with some new view of the constitution of the substance.
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The British Association . Nature 30, 548–549 (1884). https://doi.org/10.1038/030548b0
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DOI: https://doi.org/10.1038/030548b0