December 22, 1923] 



NA TURE 



901 



a list of all the hafnium lines (about 800) found 

 between 7300 and 2300 A.U., together with a detailed 

 discussion of our methods and results. In the mean- 

 time we give here a list of the strongest lines in the 

 region between 7300 and 3500 A.U. Some of these 

 lines (denoted in the table with an asterisk) have 

 already been published at the Gothenburg meeting 

 of Scandinavian Naturalists, where, on July 13, we 

 presented a list of some 20 characteristic hafnium 

 lines between 4500 and 3500 A.U. 



The spectra were produced as described in earlier 

 letters to Nature. In the table the lines are given 

 to o-oi A.U. in international A.U. in air, but- the 

 errors may amount to about 0-05 A.U. In the 

 region of the longest wave-lengths, where the accuracy 

 is less, we give the values to o-i A.U. The intensity 

 IS given both for arc and spark spectra in the usual 

 scale (i to 6). For the longest wave-lengths our 

 spark spectra were not strong enough to permit 

 us to give spark intensities, and above 5100 A.U. 

 the spark intensities are only of relative value and 

 can be compared directly neither with the corre- 

 sponding arc intensities nor with the spark intensities 

 of the shorter waves. 



As mentioned in our first letter (Nature, March 

 to, 1923), we must expect to find some of the most 

 prominent hafninni Iuk s nmoii.^ the zirconium lines 

 iiiensured before h.ilinuii: \\ >- ■ liscovered, as all com- 



Toiiiiiiii loiH' (mr-h;i!t to live per 



I 111 II in . I II t.n i 111 the M;;^liJU of the 



,> I Miiii, ■ uer and llaschek's zirconium 



' iently exhaustive, nearly all 

 lines here given among Exner 

 iniuiii spark lines as weak lines 

 SiiRc liachem (Diss. Bonn, 1910) 

 liiH's 6386, 4093, and 3505, the.se 

 i-tii,.r iiiv<>^ti<r;itinns aro mndo, 



le.i.-iiren; 



: 111 iiii I 

 /ir( 

 1 iiiieli.'Mlv i or .'. . 



ives only the thre 



llIH'S m;iV, nntil 



)(; 1,1 U' Ml 



1 11 ! ■ ■, 111 I 



itetets Institut for teor^ 

 ( opcnhagen, Novembti 



NO. 2825, VOL. I 12] 



r ll!t !lll,l tr h.i lllllllll 



H. W ■ 



S. \\! ■ 



Scientific Names of Greek Derivation. 



May I follow Prof. Grenville Cole (Nature, 

 November 17, p. 724) in supporting Sir Clifford 

 Allbutt ? The prefix " dino-," as thus spelled, is 

 ambiguous. We who know that " dinosaur " means 

 " terrible lizard " may smile at the undergraduate 

 and his " dinnosaur." But how would you pronounce 

 " Dinocystis " ? Wrongly, no doubt, as I did myself 

 until I learned that the first begetter of the name 

 derived it from Siveiv, to swirl, because the rays 

 are spirally coiled. The same for Dinocharis and 

 Dinophysa. Well, then, what about the giant cork- 

 screw shell from the Hastings Sand — the Dinocochlea 

 of B. B. Woodward ? That perhaps means " spiral 

 coil " ; or does it mean " monster coil " ? Should it, 

 in short, be Deinocochlea or Dinocochlea ? 



We may, in systematic nomenclature, feel bound 

 by the rules for transliteration recommended by one 

 or other international committee ; but in writing 

 English let us be free. Alas ! here comes the Society 

 for Pure English with its Tract XIII., and invites 

 us to print " coeval," " medieval," " primeval," and 

 " peony." Why ? If you eliminate the bouquet of 

 the grape, the wine may be the purer, but it tastes 

 no better. Already you may hear others than under- 

 graduates speak of Economics and ecological. These 

 changes of spelling do not follow the debased pro- 

 nunciation, they induce it ; and so the meaning and 

 force of words vanishes with their savour. Pure 

 English indeed ! Fortunately some impure English, 

 called slang, still has " a tongue with a tang." 



Next Prof. Cole deals with the writing and printing 

 of diphthongs. The British Museum, he reminds us, 

 writes " Moeritherium." That is because the officers 

 of its Geological Department and others long since 

 discovered that the use of digraphs (oe, ae, etc.) to 

 represent diphthongs was the most fruitful source 

 of misprints. Let us help the printers and our 

 pockets ! Otherwise I foresee the day when the 

 undergraduate will call " this fascinating creature " 

 the Merrytherium. F. A. Bather. 



Like Prof. Cole (Nature, November 17, p. 724) I 

 prefer to transliterate the Greek letters, especially 

 the vowels and diphthongs, directly into English — to 

 represent, for example, c" by ai instead of cb, and 

 61 by ei instead of i. Perhaps the worst examples 

 I know of the emasculation of Greek diphthongs 

 are the old-established Miocene and Pliocene, which 

 show not only a weakening of n to i, but also a 

 further degradation of cti to a simple e. I am afraid 

 it is too late to restore these words ; but I am sorry 

 to say that there are those who, on the specious plea 

 of consistency, wish to write Cenozoic for Kainozoic 

 and to ex lend this system of transliteration in- 

 definitely. WiiaL I his means is illustrated by the 

 fate of the two words Kaivb's and Kevh's, both repre- 

 sented by " ceno-," which in Cenozoic and Cenocrmus 

 means " recent, " and in Cenoceras and Cenosphaera 

 means " empty, a most unnecessary and unreason- 

 able confusion of distinct words. 



John W. Evans. 



An llncommon Type of Cloud. 



The type of (loud photographed by Dr. Lockyer 



(N.\tui?i:, No\eniliei 17, ]■>. 7^5) is vorv frequently 

 seen at Koc l.i ik.'inal m ^oiith India dnrin.L; tlie ihuuder- 

 slunu bca.suu m Vpiil and M.iw It is al\\.i\s associ- 

 ated with thniid< r ,11 id al\\,i\> ,ip)ie,iis after the 

 thunderclouds h.i\e expended their (deetncal energy. 

 This often h,ip]iens quite suddenly when the storm 

 is of local origin. 



2 B 2 



