June 22, 1905J 



NA TURE 



18' 



lished, thanks to the courtesy of volunteer observers. The 

 department has, however, lost no time in obtaining properly 

 verified instruments, but the difficulties may be gathered 

 from the fact that out of two consignments of grass 

 minimum thermometers only one instrument survived the 

 transport. The heights of the stations are not yet 

 accurately known; many of them have an altitude of 

 5000 feet to 6000 feet. 



The thirteenth yearly report of the Sonnblick Society 

 for the year 1904 contains an interesting account of some 

 of the results obtained at the highest mountain meteor- 

 ological stations of Europe, with photographic illustrations ; 

 the arduous work done in the interest of meteorological 

 and physical science at some of these inhospitable localities 

 has from time to time been referred to in our columns. 

 In the present report A. Edler von Obermayr discusses 

 the frequency of sunshine at the summit of the Sonnblick 

 (3106 metres) with that at other mountain stations. The 

 tables exhibit some peculiarities : — on Ben Nevis the 

 greatest frequency occurs in June, on the Obir and Santis 

 in July and August, but on the Sonnblick the greatest 

 frequency occurs exclusively in the winter months, from 

 November to February. A useful index is given in a 

 separate paper of the various items and unusual occurrences 

 contained in the Sonnblick reports for the twelve years 

 1892-1903. 



In his earliest researches on the properties of gaseous 

 fluorine, M. Henri Moissan shovv'ed that it reacted 

 vigorously with nitric acid, fluorine and the vapour of the 

 acid producing a violent explosion. In the current number 

 of the Comptes rendiis MM. Moissan and Lebeau give an 

 account of a systematic research on the reactions between 

 fluorine and the compounds of nitrogen and oxygen. 

 Nitrogen peroxide and nitrous oxide proved to be perfectly 

 indifferent towards fluorine, but a lively reaction, accom- 

 panied by flame, was found to take place between fluorine 

 and nitric oxide. With the nitric oxide in excess, the 

 gaseous products proved to be nitrogen, nitric oxide, and 

 nitrogen peroxide, the fluorine appearing in the form of 

 a solid product of indefinite composition containing 

 platinum (from the tube by which the gas was led in) and 

 nitrous compounds. But with the fluorine in excess, the 

 reaction appeared to be more definite, and a gaseous com- 

 pound containing fluorine, nitrogen, and oxygen was pro- 

 duced, the substance being solid at the temperature of 

 boiling oxygen. This solid, when allowed to boil off, could 

 be condensed to a colourless liquid at —80° C, and further 

 work is being carried out with the view of establishing its 

 composition and properties. 



A SHORT report has been received upon the present state 

 of the work done in connection with the " Technolexicon " 

 of the Society of German Engineers. In the compilation 

 of this universal technical dictionary for translation pur- 

 poses (in German, French, and English), which was com- 

 menced in 1901, about 2000 firms and individual 

 collaborators are assisting at present. Up to now 

 2,700,000 word-cards have been collected; and this number 

 does not include hundreds of thousands of cards that will 

 result from the working out of the original contributions 

 not yet taken in hand. The editor-in-chief of the 

 " Technolexicon " is Dr. Hubert Jansen, Berlin (N\V. 7), 

 Dorotheenstrasse 49, and he will be glad to give any in- 

 formation concerning the work. 



A KEY to the first part of " A New Trigonometry for 

 Schools," by Mr. W. G. Borchardt and the Rev. .-V. D. 

 Perrott, has been published by Messrs. Geo. Bell and Sons. 

 NO. i860, VOL. 72] 



OUR ASTRONOMICAL COLUMN. 



SuRS WITH Peculiar Spectra.— Mrs. Fleming has dis- 

 covered several more new variable stars and other objects 

 having peculiar spectra whilst examining the Henry Draper 

 memorial plates. The designation, position for 1900 

 magnitude and spectral peculiarities are given for each ot 

 these in No. 98 of the Harvard College Observatory 

 Circulars. Several of the objects mentioned have bright 

 lines in their spectra, and one or two call for special 

 remark. For example, a star in Cepheus at R.A. - 

 oh. 7.6m., dec. = -1-71° 32', was found to have a spectrum 

 containing five bright bands at \\ 3869, 4101, 4340, 4688 

 and 4861. The first of these coincides with the bright band 

 seen in certain gaseous nebula;, the second, third, and 

 fifth will be recognised as due to hydrogen, whilst the 

 fourth the brightest of all, corresponds to the character- 

 istic line seen in fifth-type stars. The chief nebula line 

 at \ :;ooo was not seen. Prof. Pickering suggests that 

 this object mav have arrived at an intermediate stage 

 between a nebula and a fifth-type star. 



Another star situated in the position R.A. = ih. so-^^n-' 

 dec. = -t-62'' 49', in the constellation Cassiopeia, '5 now 

 classed as a gaseous nebula, its spectrum consisting of the 

 chief nebula line at \ sooo. 



A second table in the same Circular describes the spectra 

 of twentv-one known variables, and Prof. Pickering states 

 that in 'most cases of long-period variables the bright 

 hydrogen lines are not seen during the epochs of minima. 



Variable Stars in the Clusters Messier 3 and 5.— 

 The hundredth Harvard College Circular contains a dis- 

 cus'^ion by Prof. Bailey of the variable stars discovered 

 in the clusters Messier 3 and Messier 5. These two 

 clusters contain a greater proportion of variable stars than 

 any other hitherto examined. Of every seven stars in the 

 former one is a variable, whilst in Messier 5 the ratio is 

 I • II Periods have been determined for most of the 

 variable stars, and their similarity is remarkable. Only 

 two stars, Nos. 42 and =;o in Messier 5, having periods 

 of 2S-74d. and io5-6d. respectively, appear to depart from 

 the rule all the other variables in both clusters having 

 periods differing but little from I3h. The average devi- 

 ation from the mean (i3h.) in Messier 3 is ih. om., and in 

 Messier 5 (mean I2h. 45m.) ih. 13m. All the variables 

 are of nearly the same magnitude, varying from 13.0m. 

 to i6om., and there is a slight suggestion that the periods 

 of them undergo a secular variation in length. 



Spectroheliograph Results.— In No. 4, vol. xxi., of 

 the Astrophysical Journal, Mr. Phillip Fox, of the \ erkes 

 Observatory', discusses the observations made with the 

 Rumford 'spectroheliograph during 1904. The plates 

 secured with the H, radiation, i.e. the radiation of the 

 centre of the H calcium line, show a decided increase of 

 activity in the flocculi over that observed during 1903, and 

 are being measured in order to determine the solar rotation 

 period at the height, above the photosphere, of the high- 

 level flocculi. 



Many series of plates, on which the individual exposures 

 were made at intervals of a few minutes, the successive 

 settings of the secondary slit being made in ten or twelve 

 steps from \ 39524 to \ 39686, were secured, and Mr. 

 Fox briefly discusses these in regard to the distinction 

 between facula; and flocculi in the calcium vapour images. 

 Such a series of photographs, taken on August 25, is 

 reproduced on one of the plates accompanying the paper 

 and shows that few, if any, flocculi appear in the high 

 levels without their bases appearing, although usually 

 diminished, in the lower levels. Even the bright patches 

 designated " eruptions " bv Messrs. Hale and Ellerman 

 can be traced as such as far down as the photograph taken 

 with the secondary slit set at \ 3967. The photographs 

 secured with the hydrogen radiations H3, H7, and He 

 generally show flocculi coincident with those seen on the 

 calcium photographs, and in nearly all cases w-here the 

 eruptions could be traced to the limb associated promin- 

 ences were discovered above the flocculus. 



No prominences of great height or unusual form were 

 photographed on the limb during 1904, but some of the 

 plates show a fair number, and one or two beautiful 

 examples are reproduced on the second plate of the paper. 



