276 THE POPULAR SCIENCE MONTHLY 



Although I have quoted a Weather Bureau publication — because it 

 happened to lie nearest at hand — the example selected is a fair specimen 

 of the loose language of a majority of writers on atmospheric optics. 

 In fact, the vocabulary is so confused that one can hardly write of any 

 but the commonest of the photometeors without defining each term he 

 uses; and I am not sure that even the names of the commonest are 

 wholly unequivocal. In a recent number of Nature — a journal which 

 is usually a purist in scientific English — the beautiful circumzenithal 

 arc, Mascart's " upper quasi-tangent arc of the halo of 46 degrees," was 

 referred to as a " zenith rainbow." Still more startling is it to find 

 the new edition of Wood's " Physical Optics " ignoring the term 

 " corona " altogether in describing the diffraction rings around the sun 

 and moon. 



In contrast to the prevailing confusion in the English vocabulary of 

 this subject, we find that the labors of Pernter have led to the adoption 

 of a nearly uniform terminology in recent German literature; but 

 this writer shares with his compatriots a prejudice in favor of native 

 terms that detracts much from the value of his contributions to the 

 universal language of science. Thus, while he has adopted the Greek 

 word " halo," he prefers to call a corona a " Kranz," and he clings to 

 " Hof " as a general name for the heliocentric circles of all kinds. 

 In fact, very few Greek or Latin names appear anywhere in his great 

 treatise on atmospheric optics. Of course, this fact is merely typical 

 of the almost universal preference of German science for linguistic 

 isolation ; a subject too large to enter upon here. 



In French, the complicated terminology of halos was set in order 

 by Auguste Bravais, and his labors have been admirably seconded in 

 our own time by Louis Besson. Fortunately French science still pre- 

 fers a Grasco-Latin vocabulary, and the terms it introduces are easily 

 taken over into English. No adequate account of halos has yet ap- 

 peared in our language. Whoever undertakes to write one will hardly 

 err in adopting the Bravais-Besson terminology en bloc, with only the 

 necessary idiomatic modifications and without regard to the practise of 

 earlier English writers on the same subject. 



In the brief space remaining at my disposal I think I can not do 

 better than to refer specifically to a few meteorological terms, of more 

 or less recent origin, that deserve a wider use in scientific literature 

 than they now enjoy. 



Beginning at the top of the alphabet, I find that the branch of 

 meteorology dealing with upper-air research is not yet known to all 

 meteorologists as " aerology." This term, proposed by Koppen, and 

 officially adopted at the Milan meeting of the International Commis- 

 sion for Scientific Aeronautics in 1906, is so well adapted to fill a 

 serious gap in our vocabulary that one is surprised at the slow progress 

 it has made in English. This is all the more surprising because, in 



