454 



NATURE 



\_Marck 7, 1889 



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■wire, needles, and knives ; and a number of specimens of reputed 

 pure iron, viz. Demidortf's sheet-iron, a sample of which was 

 kindly given to the authors by Mr. Crookes, electro-deposited 

 iron, and some ancient Indian iron from Prof. Roberts- Austen, 

 and iron prepared by the late Dr. Matthiessen. Also a large 

 number of iron ores — haematite Elba ore, Welsh bog ore, 

 micaceous ore, ordinary spathic ore, 

 a spathic ore found in cryolite, for 

 which the authors have to ihank Dr. 

 Midler ; Giderite, pyrites from the 

 chalk, wolfram and rouge. Iron was 

 also separated from the ignited 

 residue of blood. All the specimens 

 examined gave the same result. Fig. 

 I represents the bands seen in a solu- 

 tion of cobalt chloride to a scale of 

 wave-lengths ; the three most refrang- 

 ible bands are easily photographed, 

 but are not visible to the eye under 

 ordinary conditions. The iron spec- 

 trum (Fig. 2) in general appearance 

 closely resembles the cobalt spec- 

 trum, but the band which in cobalt 

 is at 605 is slightly shifted nearer 

 the blue, as shown in the diagram ; 

 there appears also to be a shift in 

 the 501 band, but in the opposite 

 direction. It was found that ether 

 always dissolves out of the ferric 

 chloride a substance which gave a 

 band of extraordinary intensity, ex- 

 actly agreeing in position with the 

 530 band in the cobalt spectrum ; 

 further, that on increasing the 

 strength of the ethereal solution, 

 other bands became visible, agreeing 

 with the bands observed in the strong 

 chlorhydric solution of ferric chloride, 

 and differing only in the case of the 

 690 and 655 bands, which in the 

 ethereal solution were nearer the 

 blue. Fig. 2 is the spectrum ob- 

 served in a solution of iron in chlor- 

 hydric acid, peroxidized by any 

 ordinary means. For a variety 

 of reasons the authors believe that 

 this spectrum (Fig. 2) does not 

 arise from the presence of cobalt in 

 the iron. In the first place, there 

 is a constant difference between the 

 two spectra, as shown in the posi- 

 tion and appearance of the band at 

 597. A trace of cobalt dissolved along 

 with the iron gives the same spec- 

 trum as pure cobalt dissolved in 

 chlorhydric acid. Again, on gradu- 

 ally increasing the strength of a pure 

 cobalt chloride solution, the bands in 

 the red are the first to appear, and 

 the band at 530 is not visible until 

 the general absorption has crept up 

 as far as 580, completely blocking up 

 the red end of the spectrum ; in an 

 ethereal solution from iron, on the 

 contrary, this 530 band is the first 

 to appear, and the bands in the'red 

 only become visible in comparatively 

 strong solutions. Ether extracts the 

 band-giving substance from the fer- 

 ric chloride with great ease ; but 

 It abstracts nothing from the cobalt 

 chloride. Again, on dissolving iron 

 in chlorhydric acid, no bands are 

 visible, and so long as the iron is in 

 the ferrous state even ether extracts no band-giving substance ; 

 but on converting the ferrous into ferric chloride by nitric 

 acid, or potassium chlorate, &.C., the band-yielding substance 

 is at once apparent. A known weight of Mr. Crookes's 

 Demidorff iron was converted into chloride and dissolved 

 in a known volume of ether, and the intensity of the bands 



ii 



§ 



compared with those given by cobalt chloride dissolved 

 in a similar bulk of chlorhydric acid ; it was found 

 that approximately it required a weight of cobalt equal to 

 that of the iron to give bands of similar intensity. Prof. 

 J. Norman Lockyer, F.R.S., said that some years since, in a 

 paper communicated to the Royal Society, he had suggested that 

 there were many different molecular groupings of the same 

 element possible, and that spectrum analysis would disclose 

 these : if the same molecular grouping were demonstrated in 

 several substances, then undoubtedly there was a common 

 constituent. If the bands described by the authors represent a 

 substance common to iron and cDbalt, it should be possible to 

 obtain spectroscopic evidence of its presence at some temperature 

 on volatilizing the metals ; although he had not fully studied 

 cobalt and nickel comparatively, he had, in fact, found that 

 under certain special conditions some of the spectroscopic 

 appearances were common to both, and in such a marked degree 

 as to render it improbable that they were caused by impurities. 

 Dr. Perkin referred to the non-appearance of bands in an 

 alcoholic solution of purpurin and their appearance in an ethereal 

 solution, as an illustration of the influence of the solvent. 

 Prof. Armstrong remarked that the slight shift of the bands 

 which had been referred to did not necessarily indicate thai 

 different substances were primarily the cause of the absorptions, 

 as it is well known that such effects were observed on employing 

 different solvents ; the absorbing substance mii^ht in the one case 

 be held in combination more firmly than in the other ; this view 

 was in harmony with the statement that ether did not extract 

 the band-yielding subtance in all cases. Dr. Russell in reply 

 said that not the spectrum as a whole, but only one of the bands 

 was shifted. His view was that the solvents had broken up the 

 substance into a finer state. — Note on methyl fluoride, by Dr. 

 N. Collie. Methyl fluoride assumes the critical state at 44° '9 C. 

 and at a pressure of 47,123 mm. This pressure is probably 

 slightly too high, owing to a trace of air, and the temperature 

 too low. The error in pressure probably does not exceed j 500 

 mm., and of temperature o°-2 C. —The nitration of naphthalene- 

 ;3-sulphonic acid, by Prof Ii. E. Armstrong, F.R.S., and Mr. 

 W. P. Wynne. According to Cleve three isomeric a-nitro-/3- 

 sulphonic acids are produced on nitrating naphthalene-;8- 

 sulphonic acid ; the chlorides of which melt respectively at 169", 

 140", and 125°. The authors find, contrary to the view put 

 forward provisionally by Cleve {Bcr. der DeiU. Chem. Gesells., 

 xxi. 3275), that the first compound is a heteronucleal derivative 

 and corresponds in constitution with the dichloronaphthalene 

 melting at 63°-5. All attempts to obtain the sulphochloride of 

 intermediate melting-point have been unattended with success. — 

 Action of bromine and chlorine on the salts of tetrethylphos- 

 phonium, by Prof O. Masson and Mr. J. B. Kirkland.— 

 Preparation of the salts of triethylsulphine, tetrethylphos- 

 phonium, and analogous bases, by the same. 



Linnean Society, February 21.— Mr. Carruthers, F.R.S., 

 President, in the chair.— Mr. George Murray exhibited a fossil 

 Alga, Neiuitophycus Logani, Carr. — Mr. G. C. Druce exhibited 

 some rare British plants from Scotland, amongst which were 

 Caiamagrostis boreilis. Ranunculus acris, var. pumilus, and 

 . Broinus mollis, var. dccipiens. — Prof. Marshall Ward exhibited 

 I a sclerotium of a Fungus produced from a Botrytis spore, and 

 explained the method by which it had been obtained.— A paper 

 was then read by Mr. F. Townsend, M.P., on Euphrasia offici- 

 nalis, with a description of a new sub-species, and a discussion 

 followed, in which the President, Mr,- J. G. Baker, and others 

 took part. -In the absence of the author, a paper by Mr. C. T. 

 Druery, on sexual apospory in Polystichuin angiilare, was read 

 by the Botanical Secretary, Mr. B. J^. Jackson, upon which 

 remarks were made by Mr. Murray and Dr. D. H. Scott. — Mr. 

 Murray then gave the substance of a paper on a new genus of 

 Green Algas, proposed to be named Boodlea, and in so doing 

 made some instructive observations on the affinities and dis- 

 tinguishing characters of allied j;enera. The paper was criticized 

 by Messrs. A. W. Bennett, Reay Greene, and D. H. Scott. — 

 In continuation of his researches upon the eyes of insects, Mr. 

 B. T. Lovvne gave an admirable exposition of the structure of 

 the retina in the blow-fly, illustrated by preparations under the 

 microscope, and some excellent photographs. 



Geological Society,February 15.— Annual General Meeting. 

 —Dr. W. T. Blanford, F.R.S., President, in the chair.— The 

 Secretaries read the reports of the Council and of the Library 

 and Museum Committee for the year 1888. The Council stated 



