204 



NATURE 



\yune 30, 1 88 1 



fluorine. When the mineral is broken up, a strong chlorine-like 

 odour is perceptible ; when heated with sulphur, an odour re- 

 sembling that of sulphur chloride is evolved ; the liquid in tlio 

 mineral decoaiposes sodium chloride and iodide, with forma- 

 tion of chlorine and iodine respectively. On addition of dilute 

 potash it yields a solution which instantly decolorises indiu;o 

 solution. When the mineral is moistened with ammonia water, 

 powdered, the liquid filtered off, neutralised with sodium cu- 

 bonate and evaporated, a residue is obtained which, on addition 

 of sulphuric acid, evolves hydrofluoric acid. Herr Low thinks 

 that the fluorine is produced by dissociation of cerium fluoride 

 in the mineral. 



The application of potassium oxalate as a precipitant for many 

 heavy metals, both in qualititive and quantitative analysis, is 

 described by Herr von Reis in the Berichte of the German 

 Chemical Society; the -quantitative results obtained are very 

 accurate. 



The reaction of bleaching"povvder on alcohol, which results 

 in the formation of chloroform, is not thoroughly understood. M. 

 Bechamp details experiments (AnnaUs Chini. et Phys.), according 

 to which no oxygen is evolved during the change, but only after 

 the primary change is complete, and a secondary change begins 

 when the reacting bodies have acquired a high temperature. 

 The formation of chloroform is represented by M. Bechamp by 

 the following equation, iC^W^P -I- 4Ca{OCl).^ = CaCl„ -1- 2H„0 

 -t- 2Ca(0H)j + (HC02)oCa -1- 2CHCI3. 



In Amiali di Chimica Signor Chlappe states that he has 

 found spots of minium (Pb.jOj) on various marble monuments, 

 on parts of which bands of lead have been fastened. He sup- 

 poses that by the action of the air and rain lead carbonate is 

 produced, this is absorbed by the marble, and when exposed in 

 places to the sun's rays it is decomposed with production of 

 minium. 



A VARIETY of coal, said to be the most highly-carbonised 

 member of the coal series hitherto described, has been found 

 near Schunga, on the western shores of Lake Onega {Jahrbuch 

 fiir Mineralogie] ; it contains about 91 per cent, carbon, 7 or S 

 per cent, water, and i per cent. ash. This coal is extremely 

 hard and dense, has an adamantine lustre, is a good conductor of 

 electricity, and has a high specific heat {0-1922). Although 

 containing as much carbon as the best graphites from Ceylon, it 

 is not a true graphite, inasmuch as it is not oxidised by potasMum 

 chlorate and nitric acid, but behaves towards those reagents like 

 an amorphous coal, 



Feder and Voit have carefully repeated the experiments of 

 Hallervorden on the effect of feeding with ammonium carbonate 

 [Zatschrift fiir Biologie). The results confirm the statement of 

 the last-named author, that in dogs ammonium carbonate is con- 

 verted into urea, and also show that ammonium acetate under- 

 goes a similar change. 



It has been asserted that the employment of sodium nitrate in 

 manures facilitates the solution and removal from the soil of 

 plant-foods : Herr Fiedler has recently examined thii subject 

 experimentally, and he thinks himself justified in concluding 

 that nitrates do not dissolve out any considerable quantities of 

 plant-foods from the soil ; that, within certain limits, absorption 

 of pho-phoric acid is favoured and absorption of potash slightly 

 impeded by sodium nitrate; and that the same salt exerts a 

 solvent action on dibasic phosphates of calcium, iron, and 

 aluminium, but not on the tribasic phosphates of these metals. 



GEOGRAPHICAL NOTES 

 At the meeting of the Geographical Society on Monday last, 

 Lieut. -Col. C. E. Stewart, of the Bengal Staff Corps, read some 

 portion; of a paper which he had prep.ared on the country of the 

 Tekke Turkomans and the Tejend and Murghab Rivers. Col. 

 Stewart, it may be remembered, is one of the officers who was 

 accused, in a recent official despatch from St. Petersburg, of 

 "haunting the oases " in the Turkoman country : this paper was 

 consequently looked forward to with much interest. He left 

 Constantinople in April of last year, and proceeded in the first 

 instance to Ispahan, where he spent two months and a half in 

 the Armenian quarter of Julfa, making preparations for his 

 jouruey, as he had determined to travel in the disguise of an 

 Armenian horse dealer. On September 30 he w ent to Ardakan, 

 where he assumed his disguise, and travelled in a north-easterly 

 direction along the edge of the salt desert to Meshed, afterwards 



crossing the mountains to Mahomedabad. The account of this 

 part of his journey, with its numerous adventures. Col. Stewart 

 was unfortunately obliged to omit, owing to the length of his 

 paper. Deregez, in which Mahomedaliad is situated, is in the 

 most northern part of North-east Persia beyond the mountains, 

 and is some sixty-five miles long and forty broad ; as it projects 

 into the Turkoman country, it is a most favourable position for 

 collecting information respecting the neighbouring country to 

 the Caspian on one side, and to Merv on the other. Col. 

 Stewart made Mohamedabad his head-quarters from November 

 25 to January 15, and during this time moved about in Deregez, 

 but never crossing the Persian frontier, and obtained much inter- 

 esting infoi-mation by diligent inquiry among the Persian officials 

 and the Turkomans whom he met. This particularly applies to 

 the Merv district — for he denies the existence of a town of Merv — 

 and the Murghab River. Col. Stewart also explained very 

 clearly the Russian line of advance, and the present and future 

 position of the railway question. It may be interesting to add 

 that his disguise was completely successful, and entirely deceived 

 even the Persian serv.mt of Mr. O'Donovan, the enterprising 

 correspondent of the Daily News, who is now detained in the 

 Merv district. 



The fiftieth and last volume of the Geographical Society's 

 Journal is chiefly occupied with Mr. C. R. Markham's history 

 of the fifty years' work of the Society, which is at once valuable 

 and entertaining. In it will be found detailed the actual circum- 

 stances ai tending the establishment of the Society, about which 

 some misapprehension has hitherto prevailed. This took place 

 in July, 1S30, and the Society is therefore now fifiy-one years 

 old : after passing through many vicissitudes, which at one time 

 threatened its very existence, it now numbers 3394 ordinary 

 Fellows, and is the largest and wealthiest institution of the kind 

 in the world. Mr. Markham, we may add, has been able to 

 reproduce its first list of 460 Fellows, dated August 4, 1830. In 

 a voluminous appendix, equal in length to the history, he fur- 

 nishes complete lists of ofiicers from the commencement, refer- 

 ences to obituary notices of distinguished men, lists of explorers 

 and geographers who have received medal*, grants m aid 

 of their work, &c., and of the papers and maps published 

 by the Society. Lastly there is some interesting informa- 

 tion respecting the Hakluyt Society. The few remaining pages 

 of the volume contain notes on two maps of the Andaman 

 Islands by Mr. E. H. Man and Lieut. R. C. Temple, and on 

 the history and origin of the word " Typhoon," by Dr. F. Hirth, 

 tables of altitudes in East Central Africa computed from 317 

 observations taken by Mr. Joseph Thomson during his recent East 

 African expedition, and a narrative of a journey overland from 

 Amoy to Hankow by Mr. E. F. Creagh. From a brief prefa- 

 tory notice we learn that the issue of the Journal is to be dis- 

 continued, and that in future " elaborate papers of more than 

 ordinaiy length and great value " will be published as supple- 

 ments to the monthly Proceedings. 



From the Colonies and India's Queensland notes we learn 

 that Mr. Watson, in command of the Transcontinental Railway 

 .Survey, had crossed the Worna and Workingham Creeks in 

 safety, and reported the soil magnificent and the grass splendid. 

 The floods had however " sadly hampered the expedition," and 

 this fully bears out the remarks made in Nature, vol. xxiv. 

 p. 114, as to the route for the line laid down on the Government 

 map. It has lately been announced that General I'ielding and 

 Mr. J. Robinson, C.E., have gone out to make what is presum- 

 ably an independent survey for a line, and we hope they may be 

 able to find a more suitable route. The arriv.il of Mr. Watson's 

 party at Pc^int Parker, on the southern shore of the Gulf of 

 Carpentaria, has since been announced by telegraph. 



The new Bulhtin of the Bordeaux Society of Commercial 

 Geography contains an address recently delivered before it by 

 Capt. Gallieni, on his expedition, chiefly for surveying purposes, 

 from the Senegal to the Niger. It is accompanied by a sketch- 

 map of the region, on which the routes of the expedition are laid 

 down. 



PROF. ROWLAND'S NEW THEORY OF 

 MAGNETIC ACTION 

 DROF. ROWLAND has lately published in the American 

 -"• Journal of Mathematics (vol. ii.. No. 4 ; vol. iii., Nos. I 

 and 2) a series of papers on " The General Equations of Elec- 

 tromagnetic Action with application to a New Theory of Mag- 



