232 



NA TURE 



yjuly 8, 1880 



the ^connection between the two basins were to be established, 

 some of the mast flourishing cities of the Schott region, lil;e 

 Tooser and Nephta, would be submerged by the floods, and 

 most probably all the large date-tree forests of the Djerid de- 

 stroyed by the change of climate and the increased moisture. 

 Herr von Hesse Wartegg spoke at length of his travels through 

 the Regency, and mentioned some curious meteorological and 

 botanical observations. The traveller brought back with him a 

 large collection of plants, ethnological objects, and insects, as 

 well as drawings and photographs. He will exhibit his collec- 

 tionjat his lecture before the British Association at the forthcoming 

 Swansea meeting. 



The new number of the Geographical Society's Proceedings 

 opens with the presidential address on the progress of geo- 

 graphy, in which the chief space is devoted to the Arctic region* 

 and Africa ; it is supplemented, however, by a summary of 

 Admiralty and Indian surveying operations. A letter is next 

 given from Mr. James Stewart of Livingstonia to the Free 

 Church of Scotland, furnishing a further account of his recent 

 explorations north-west of Lake Nyassa, up to the south end of 

 Lake Tanganyika, and which was accompanied by valuable 

 longitude observations. The latter is illustrated by Mr. Stewart's 

 route surveys, which are of great value from a geographical 

 point of view. Among the notes information is given respecting 

 Dr. Lenz' progress in North-Western Africa, which had reached 

 the Foreign OfiiL:e through the British Minister at Tangier. Dr. 

 Lenz is stated to have crossed the Atlas, and Moorish protection 

 being refused him beyond Terodant, he has pushed on alone 

 towards Timbuctoo and the Soudan, disguised as a Mohammedan 

 doctor and accompanied by a Moor named Hadj Ali. There 

 are also interesting particulars respecting the movements of a 

 Roman Catholic missionary expedition to the Matabele country 

 and the Upper Zambesi region. 



SiGNOR Fraccarolf, the delegate of a society formed last 

 year at Milan for the development of commerce with Central 

 Africa, has lately paid a visit, in company with Emiliani Bey, 

 to the centre of the Darfur province, which he found in a state 

 of desolation from the recent wars. After a vain attempt to 

 reach the summit of Jebel Si, a lofty isolated peak in the Jebel 

 Marra, he returned to Khartum, whence he expected to proceed 

 on a journey up the Balor el Ghazal. 



Count Louis Pennazzi is about to undertake a journey in 

 Abyssinia and the neighbouring region. He proposes to start 

 from Massowah and visit the city of Gondar and Mount Debra 

 Tabor, hoping to find King John and obtain from him an 

 escort to accompany him through the Gojam province and to the 

 Blue Nile. Thence he will proceed in a west-south-west direc- 

 tion, following the Sobat and the White Nile along the eighth 

 parallel, and eventually join Signor Gessi. 



NEW METALS 

 ■yiT'ITHIN a period of about two years the chemical world has 

 teen startled by the successive announcement of the 

 discovery of no less than fourteen ' new elementary bodies. All 

 of them are classed as metals, and eleven are said to belong to 

 the yttrium or to the closely-allied cerium group. Without 

 pausing to examine the advisability of announcing the discovery 

 of a new element whenever an unknown reaction crops up, we 

 purpose to give a brief account of these discoveries, and to 

 investigate, as far as possible, what claim they may have to be 

 honoured with a place in our lists of the chemical elements. 



In July, 1S77, M. Sergius Kern published- the discovery of a 

 new metal belonging to the platinum groups, to which he gave 

 the name davyiiin. The davyum was, he said, contained in the 

 latter portions of the platinum ores precipitated by hydrogen at 

 100° together with the rhodium and iridium. The metals having 

 been heated with barium chloride and chlorine in the usual 

 manner, the rhodium and iridium were fractionally precipitated 

 by acid sodium sulphite, and the davyum contained in the filtrate 

 thrown down with ammonium chloride and nitrate. From this 

 double chloride an ingot of the metal weighing 0-27 gramme was 

 obtained. The properties of this metal and its compounds, as 

 stated by M. Kern, all agree more or less closely with those of 

 the other platinum metals. It is difficultly fusible, dissolves 

 only in aqua regia, possesses an atomic weight of about 100, &c. 



' '''■ f-<^<:oq de Boisbaudr.iirs ^a///««/. ihc existence of which has now 

 been fully established, is not included in this number. 

 2 Chemical News, vol. xxxvi. p. 4. 



Its specific gravity is, however, said to be 9'3S, which is lower 

 than that of any other metal of this group, but approximates to 

 a mixture of rhodium with a Utile iron. The characteristic 

 reaction is stated to be the red colour produced by potassium 

 sulphocyanate, but unfortunately both iron and ruthenium 

 produce the same result, and M. Kern does not tell us what 

 means he has adopted to get rid of traces of these and the other 

 platinum metals, or to convince himself that they were absent. 

 It is to be regretted that no protest, except a letter of Mr. W. H. 

 Allen,' has been raised against this endeavour to foist a "new- 

 metal " upon the chemical world, and that too by a chemist who has 

 signallised himself by such inaccurate results in other directions. 



Turning now to the recent additions to the yttrium metals, we 

 have in the first place to notice a contribution by Marignac. 

 In the summer of 1S78, after examining the earths from gado- 

 linife to e-tablish the existence of terbium, this chemist was 

 induced to attempt a further separation of the erbia obtained in 

 the course of his experiments. These investigations led to the 

 discovery that this pink earth contained another white earth with 

 a somewhat higher atomic weight, and whose salts gave no ab- 

 sorption-spectrum. To the metal contained in this earth the name 

 yttaiiium - was given. These results have recently been fully 

 confirmed,^ and we may accept the existence of this metal as an 

 established fact. Marignac gave some of his specimens to his 

 colleague, M. .Soret, to examine spectroscopically. The latter 

 chemist, operating with sunlight and with a spectroscope of high 

 dispersive power, found that certain lines in their absorption- 

 spectra did not agree with those of erbia, and that this was 

 particularly the case w ith regard to the violet and ultra-violet 

 portions of the spectra. From these results he was led to 

 suspect the presence of two new earths, one of which he named 

 provisionally X, leaving the other unnamed. •■ All attempts to 

 separate either of these earths were, how'ever, futile. 



Shortly afterwards Lawrence Smith ipublished ^ the results of 

 some investigations on these earths obtained from the mineral 

 samarskite, abundant in North Carolina and other American 

 localities, instead of from gadolinite. As the result of his inves- 

 tigations he announced the discovery of a new earth, to which, 

 however, he gave no name. It was, he said, a yellow earth 

 possessing most of the properties of terbia, but differing from it 

 in some reactions. Marignac, who received a sample of this 

 earth, found,'' on examining it, that its properties did not difier 

 appreciably from those of terbia, and we may very well accept 

 the verdict of this distinguished chemist. Lawrence Smith also 

 stated that the earth called X by Soret had been discovered by 

 him in samarskite about a year previously, and had been named 

 inosandrtim. He has since admitted'' that the salts of this 

 metal give no absorption-spectrum, and he has furnished us with 

 no details as its special properties, mode of separation, &c., 

 ^vhich are conclusive enough to admit of its immediate recog- 

 nition as a new metal. 



We now come to a number of " new " metals all belonging to 

 the same group, and mainly distinguished by slight differences 

 in the absorption-spectra of their salts and in their atomic 

 weights. The earth named X by M. Soret, as well as the 

 one he left unnamed, have been already referred to. Besides 

 these, two new metals have been announced by M. Delafontaine,® 

 which he has named ptiillipium and decipititii. The former is a 

 yell iw earth with an equivalent between that of yttria and terbia, 

 the latter a white earth with a higher equivalent ; both possess 

 indistinct absorption-spectra. M. Soret, who has examined the 

 absorption-spectra very carefully, thinks it ^probable ^ that the 

 mixture formerly known as erbia may contain phillipia or his 

 unnamed earth, together with the earth X and the real erbia, 

 besides other earths giving no absorption-spectra. Of decipium 

 we have no confirmation. These earths have also been investi- 

 gated by Cleve, in conjunction with Thalen. They came to the 

 conclusion that there are three distinct earths which yield 

 absorption spectra in the old erbia.^" These they named thulium, 

 Jielinium, and the real erbium. Subsequently they have admitted ' ' 



^ Chemical Nirtus, vol. xxxvi. p, 33. 



- Arch, des Set., phys. ctnat., vol. Ixiv. p. loi. 



^Nilson, Bcr. d. dent. ch. Ccsell., v. xii., p. 550; Humpidge, Brit. Ass. 

 Reports for 1879': Lecoq de Boisbaudran, CotKp. Rend., vol. Ixxxviii. p. 

 1342. 



■* Arch, des Set., phys. et nat., vol. Ixin. p. 99. 



5 Coiiip, Rend., vol. Ixxxvii. p. 146. 



^ Arch, ties Set., phys. et nat., vol. Ixiii. p. 172. 



'' Coiup. Rend., vol. Ixxxix p. 478. 



S Camp. Rend., vol. Ixxxvii. pp. 559, 632. 



') Arch, ties Sci. , p/iys. et uat., vol. Ixiii. p. 99. 



^° Coinp. Rend., vol. Ixxxix. p. 47S. 



■' lliid., vol. Ixxxix. p. 708. 



