Sept. 4, 1879] 



NA TURE 



435 



News from tte village of Ilavnen, Iceland, states that a 

 violent volcanic eruption was observed at the end of May in the 

 vicinity of the jo-called Geisfugle shears, in the south-west of 

 the island. It is curious that about the same time the eruption 

 of Mount Etna took place. 



The first volume of a remarkable botanical work entitled 

 " Versuch einer Entwickelungsgeschichte der rflanzenwelt, 

 insbesondere der Florengebiete seit der Tertiiirperiode," by Dr. 

 Ad. Engler, of Kiel, will be published next month by \V. Engel- 

 mmn, of Leipzig. 



The Rev. S. J. Whitmee informs ns that he has received 

 letters from the Society Islands assuring him there was no such 

 devastation of the islands of Raiatea and Borabora (Porapora) 

 by earthquake as was reported by Capt. Evers, and which is 

 mentioned in the article "On Volcanic Phenomena during 1878," 

 in Nature, vol. xx. p. 378. No reference, he reminds u?, is 

 made in the article to the pumice and torn-up trees, carried 

 apparently from the island of Birara, southeast to and beyond 

 the Ellia Atolls, which he reported to us some months ago. 



A CORRESPONDENT informs us that the observer of the Scottish 

 Meteorological Society in Ireland reports fine weather there in 

 June and July, with little or no rain, by which the pastures have 

 suffered severely ; but the fishing at most places is good, in 

 direct contrast to what has prevailed in the British Isles. 



The City and Guilds Institute having granted 4C0/. per annum 

 fcr purposes of technical education at University College, 

 London, have resolved that the grant be appropriated in main- 

 taining the chair of Chemical Technology, and that of Engi- 

 neering and Mechanical Technology. The Professor of Chemical 

 Technology, Dr. Charles Graham, has announced "Technical 

 Education" as the subject of his public lecture at the College on 

 October i. 



An experiment before the Parisian press was tried on August 

 28, in the large room of the St. Lazare Railway Station, by a 

 company started for establishing a Central Hall of Telephony 

 under the Edison patent. The experiments were found quite 

 satisfactory for musical instruments, but not so for the ordinary 

 voice. The Company has received from the Government 

 authority to inaugurate its operations, and a sum of 2/. per 

 month is required for the use of a wire with the right of inter- 

 changing communications with any person having a wire directed 

 to the Central Hall. 



A SPECIAL excursion tour for members of the French Parlia- 

 ment has been organised to Algiers. The members will start in 

 this month, and devote their vacation to the study of the land 

 on behalf of which they are to legislate. The Municipal Council 

 of Algiers has voted a sum of 2co/. for the reception of their 

 legislators. 



We take the following statements from a preliminary com- 

 munication made to the Vienna Academy of Sciences by Ilerr 

 G. L. Ciamician, with reference to the further results of his 

 spectroscopic investigations : — " If the spectra of the met.ils of 

 the alkaline earths are produced by the spark of an induction 

 apparatus (with inserted Leyden jar) passing between the metals 

 ns electrodes in a hydrogen tube, then spectra are obtained 

 which show the homology of the spectral lines in a most beauti- 

 ful manner. The spectrum of magnesium, however, cannot be 

 compared to the spectra thus obtained because it does not con- 

 tain the le s refrangible lines. If, honever, the I.cyden jar be 

 removed, or if a weaker battery and a smaller induction coil be 

 employed, all red and yellow lines in the spectra of calciun) and 

 strontium will disappear and spectra are obtained which are ex- 

 tremely similar to that of magnesium. If the less refrangible 

 part of the spectrum of the group of alkaline earth-metals, which 

 therefore is only visible"at a high temperature (corresponding to 



a high electric tension), be compared to the less refrangible half 

 of the complete oxygen spectrum, the remarkable similarity of 

 these two spectrum-halves will at once strike the observer. The 

 inference to be drawn from these facts would seem to be that 

 the spectrum of the group of alkaHne earth-metals is composed 

 of the magnesium spectrum and of the less refrangible half of 

 the oxygen spectrum. 



A NUMBER of interesting observations made during a recent 

 cruise of the French frigate La Magicienne, to various parts of 

 the Pacific, chiefly formed the subject of a recent paper by 

 Admiral Serres to the French Academy. Among other points 

 attention had been drawn while at San Francisco to the swift 

 tall-masted clipper ships which convey wheat to the European 

 market. The modern practice of increasing the high sails at 

 the expense of the lower is justified by science. During the 

 voyage of La Magicicnne, a Robinson anemometer w-as observed 

 daily at an altitude of 8 metres, and twice every day the same 

 instrument was observed at 36 metres. With very rare excep- 

 tions the velocity of the wind was always found much greater in 

 the latter case than in the former. The average ratio deduced 

 from thousands of observations was about 12 to 10. One can 

 thus see the reason of seeking motive force in the upper regions. 



Pursuing his researches on the scintillation of stars, M. 

 Montigny shows, in a recent note to the Belgian Academy, that the 

 following conclusion may be formulated : — When, in those ob- 

 servations where the colours characterising the phenomenon are 

 distinctly separated, the blue tint predominates or is found in 

 excess, rain may be expected, if it have not already come. There 

 is great probability that the rain will be the more persistent and 

 plentiful the more marked the predominance of blue. M. 

 Montigny recalls the observations of P. Secchi, M. Janssen, and 

 Prof. Plazzi Smyth, according to which the telluric lines of the 

 solar spectrum increase in number and intensity in circumstances 

 where the solar rays encounter a larger quantity of aqueous vapour 

 in the atmosphere, either as the sun nears the horizon, or as the 

 humidity of the air increases. Prof. Smyth bases predictions of 

 rain on certain telluric bands in the spectrum, which he calls 

 rain- binJs. M. Montigny thinks there is no doubt that similr.r 

 phenomena of absorption are produced in the case of certain rays 

 emanating from the stars, where these traverse more or less 

 moist layers of our atmosphere. 



An apparatus called the " telephone syren" has been recently 

 described to the Schleswig-Holstein Society of Natural Sciences 

 by Herr Karsten. On a circular disk 10 ctm. in diameter are 

 fixed radially twenty-four small magnetic bars. This disk is 

 rapidly rotated before a Bell telephone deprived of the iron 

 plate. Where the same poles of the magnets are all directed 

 outwards, one hears a certain tone ; if the poles alternate, the 

 lower octave is heard. If the succession of poles at the border 

 of the disk be (say) N N S, there are heard three tones : oi-.e 

 corresponding to the interval N N, one an octave lower corre- 

 sponding to N S N, and a third combination-tone of three times 

 the time of vibration of the highest, corresponding to the return, 

 each time, of the first N. The vibration-numbers are thus as 

 3:2:1. Similar experiments may be made with the combina- 

 tion N N N S, where tones are obtained with the relation 

 4:2:1. 



The additions to the Zoological Society's Gardens during the 

 past week include a Vervet Monkey (^Cercopithcciis lalandii) 

 from South Africa, presented by Mr. W. T. Millar; a Rose Hill 

 Parrakeet (Plalycacus eximius) from New South Wales, pre- 

 sented by Mr. Arthur Stirling ; a Common Kestrel ( Tinnunculus 

 ahutdarius), British, presented by Mr. R. Moon ; a Chequered 

 Elaps (Elap lemnisca'.us) from South America, presented by Dr. 

 A. Stradling ; an Annulatcd Snake (Lep'.odira antiulaia) from 

 Colon, presented by Mr. R. F. Davis ; three Horned Lizards 



