NOMENCLATURE

WORDS ABOUT WORDS

Lipide versus Lipid

There is some confusion as to the cor­rect spelling of this word. The British and American chemical societies spell it "lipide," but manv biochemists, especially in this country, „jem to prefer "lipid." What are the facts?

The term was introduced, along with "glucide," "protide," and other terms, as part of a classification proposed by Gabriel Bertrand of the Institut Pasteur in 1922. The proposals were adopted by the In­ternational Union of Pure and Applied Chemistry (I UP AC) but met with oppo­sition, and in 1930 the union declared that the adoption was not definitive. The Ber­trand names were spelled -ide in French and were so translated into English at the time. In German "lipide*' became Lipid (plural Lipide), as was proper. The sys­tem as a whole has had much French sup­port but has not been generally accepted. "Lipide," however, has proved popular, replacing the older "lipoid" and "lipin," with a better defined meaning. In English the spelling "lipid" has crept in and now disputes the field with "lipide." Why?

One possibility is, that biochemists have been influenced by the German spelling, taking it over from German articles. Years

AUSTIN M. PATTERSON* ago it was common for Americans to go to Germany for organic chemistry, and we know that -id spellings, such as "amid" and "acetanilid," were imported in this way. German literature is still read and still has an influence. There is also an­other theory, an attractive one. There is in the biological sciences a legitimate English suffix -id which we know in such words as arachnid, carotid, hydatid, and orchid but which is quite distinct from the chemical suffix -ide. Is it not possible that biochemists have been so affected by these words that the -id spelling seems to them more "natural" than -ide?

It is not hard to show that the -ide spelling is the one legitimate one in Eng­lish for such words as chloride, sulfide, amide, anilide, glucide, lipide, and what have you. In 1787 Lavoisier and his as­sociates, in their new nomenclature, pro­posed the name "oxide" for a compound of a metal with oxygen. This spelling was taken over into English (although the French spelling was later changed to "oxyde"), and the -ide ending was gradu­ally extended to other binary compounds, replacing the earlier -ure and -uret. The variant -id appeared early, for George Pearson wrote in 1799: "We hear some

persons who ought to be more correct, say, oxid for oxide, sulphat for sulphate"; and h e stigmatized as incorrect oxid, oxyd, and oxyde, instead of oxide.

In 1889—91 a committee of Section C of t h e American Association for the Advance­ment of Science made spelling recom­mendations which, among other things, favored the -id spellings, as oxid, chlorid, sulfid. On the strength of this report these spellings appeared in American diction­aries, being even preferred by some, but they are seldom seen now in chemical books and articles. If our information is correct they were never used in England. Examination shows that authors who write "lipid" usually spell peptide, glucoside, phosphatide, and similar terms in the usual -ide way. Will they not help us make the -ide spelling unanimous? It is an error to suppose that there is an -ide ending for inorganic terms and an -id ending for organic and biochemical terms. Pronounce -ide, by the way, as in ride, not as in rid.

Petrochemical, Petrochemistry Petrologists, the fellows that deal with

rocks but aren't bankers, are complaining that petroleum chemists have stolen a couple of terms from them and are putting them to a wrong use. They point out that "petrochemistry" means "the chem­istry of rocks" and not "the chemistry of petroleum," and they cite instances of the proper use of "petrochemistry" and "petro­chemical" by petrologists and geologists. Oil chemists w h o have been consulted agree that their own use of the terms is incorrect but are afraid that this use has gone too far to b e stopped. Is it ever too late to try to correct a wrong practice? "Petrolochemicar* and "petrolochemistry," as well as the plain "petroleum chemical" and "petroleum chemistry" have been sug­gested as substitutes. Correction of the wrong use seems to b e chiefly up to the petroleum chemists; they can do more about it than anyone else. Stewart S. Kurtz, Jr., Sun Oil Co. , Norwood, Pa., is chairman of the nomenclature committee of the ACS Division of Petroleum Chem­istry and has taken an interest in the mat­ter. Eàrl Ingerson, chief of the geochem­istry and petrology branch of the U. S. Geological Survey, is one of those inter­ested from the other end.

15,000 Man Hours People who have not served < nomen­

clature committees have perhaps little idea of the time required to propose a well considered revision of the terms used in any special field. Such a report usually goes through several drafts, with study and discussion by a number of skilled chemists at each stage and consultation with many other specialists. The chair­man of a committee which reported at Buffalo, on being asked to estimate the time the work had taken, gave a figure of 15,000 man hours on only one top ici Surely w e o w e a b ig debt to busy persons who give their time and thought to improving chemical names. Some may question its value, but in the end it will mean a sav­ing of time to all chemists. ° 221 North King St., Xenia, Ohio.

A N D E N G I N E E R I N G N E W S 1910 C H E M I C A L

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