MINERALOGICAL CHEMISTRT M in e r a1o gi c a1 C h e rn i s t r y. Tungsten Minerals from Meymac (Corrbze). (Fourth Note.) By AD.CARNOT (Compt. rend. lxxix 637-640). WoZfmm.-Occurs in lamellated masses with an easy and brilliant cleavage ; no well-defined crystals have yet been noticed. Not mag- netic. Density 6.54. Average composition :-WO,. FeO. MnO. CaO. MgO. Td05. H20. 74.25 15.85 6.51 0.80 0.04 1-10 0.70 = 99-25. Some specimens contained about 5 per cent. of tantalic acid. 8cheeZife.-Tungstate of lime found in masses having a crystalline texture. Lustre vitreous to adamantine. Fracture lamellated often iridescent. The relative proportions of tungstic acid and lime lead to the formula Ca0.W03. The mineral sometimes contains a little tantalic acid.Hydrated Tzmgstic Acid.-Results from the decomposition of the Scheelite. Lustre resinous. Friable between the fingers. Colour yellow to brown. Ammonia partially dissolves out the tungstic acid. Analysis of three samples gave :-I and 11. Friable. Yellow or brownish-yellow. Powder yellow. Sp. gr. 3-80. 111. Hard. Fracture lamellated. Powder yellowish. Sp. gr., 4.54. I. 11. 111. Tungstic acid ............ 71.85 74.25 75.12 Tantalic , ............ 1.00 1.05 0.70 Lime .................... 2.50 4.65 7-00 Oxide iron.. .............. 6.00 6.10 6.25 , manganese.. ........ 0.75 0.65 0.32 Water. .................. 12.93 11.75 6.85 Gangue .................. 4.50 1-85 2.50 99.53 100.30 98.74 Deducting the calcium tungstate and ferric hydrate which may be regarded as merely admixed there remain for the proportion of tungstic acid and water numbers which may be repreaented by one of the formulee 2W03.5H20,or WO3.2H20.To decide between these two formulae new analyses will be required ; but the preceding numbers viewed in connection with the decided differences between the physical characters of this mineral and those of anhydrous tungstic acid (tungs-tite) are sufficient to show that the former is really a distinct species. The author designates it as Meynzncite. C. H. P. ABSTRACTS OF CHEMICAL PAPERS. Warwickite. By J. LAWEENCE SMITH (Compt. rend. lxxix 696-698). THEfollowing are the results of a new analysis of the mineral made by the author :- Found.Oxygen. Oxygen-ratios. Compositionassigned. Percentagetalculated. Boric.acid .. 27.80 19.06 9 3&03 30.57 Titanic acid.. 23.82 Magnesia. ... 36.80 Oxide of iron. 7.02 10.37 14.46 2.10 5 6 1 2Ti0 SMgOFeO 23-58 35.36 10.49 Silica . . . .. Alumina .... 2.21) Impurities. 100.00 He suggests the formula 5Mg0.3B,03 + (Mg0,Fe0)2Ti02 and remarks that warwickite is the only known boro-titanite in nature. R. R. Native Cuprous Sulpharsenate. By R. W. EM E xsoN MAc IY o K (Chemical News xsx 103). A SPECIMEN of Swiss dufrenoysite crystallised in small monometric crystals of a dark grey colour of sp. gr. 5.52 yielded on analysis (small percentages of lead and iron sulphidcs being neglected)- a;. 43. As. S. 46.05 2.43 18.79 32.46 = 99.73 If the 2.43 per cent.of Ag be replaced by Cu the composition agrees with t,hat required for cuprous sulpharsenate CuS(AsSp),tending to prove that tfhis mineral is dimorphous as enargite has also the formula CU,(ASS~). E W. P. Investigation of a New Fossil Resin. By K. HELBING (Ann. Chem. clxxii 297-303). THISmineral was found in a quarry at Engenau near Heilbrunn in a tertiary formation of the age of the gypsum of Montmartre. This formation usually contains no organic remains except marine alilgne ; but as both the fragments of resin and the iron pyrites which accompanies them have externally a smooth polished surface ; they are probably of organic origin. The resin is of a dark brown colour with resinous lustre and conchoidal fracture and is faintly transparent at tlre edges.It is easily reduced to a yellowish-grey powder. It remains solid up to 300" but melts when heated on platinum foil and burns with production of a large quantity of carbon while the burning pro- ducts give out a pleasant aromatic smell. It is mixed with iron pyrites in so fine a state of division that it becomes visible only on levigation. The percentage composition is- NINERALOQICAL CHEMISTRY. 47 I. 11. 111. C ............ 74.15 74.68 75.01 H ............ 9.53 9.60 9-51 0............ 1.91 1.11 1.37 FeS2.......... 1441 14-61 14-11 The resin is partly soluble in ether and in hot alcohol and can thus be divided inlo three parts. The part soluble in ether but not in alcohol amounts to about 19 per cent. ; that soluble in ether and hot alcohol to about 9 per cent.; and that insoluble in both to about 72 per cent.The soluble parts are also taken up by carbon bisulphide benzene and chloroform. The insoluble part after removal of the pyrites gave on analysis-I. 11. C.. ............ 88.21 88.46 H.... .......... 11-22 11.25 -I_ 99.43 99.71 This would indicate a hydrocarbon answering to the formula Cd0HKR2 which might be derived from a terpene CloH6, by the removal of two atoms of hydrogen. The part soluble in ether but not in alcohol melted at 19a0 and gave on analysis- I. 11. 111. C.. .......... 82.84 83.59 83-70 H ............ 11.53 11.28 11-17 o............ 5.63 5-13 5.20 These numbers point to the formula C40H6202, which would be de- rived from the hydrocarbon above mentioned by replacing two atoms of hydrogen with two of hydroxyl.The part soluble in hot alcohol and ether softens at 70° and on further warming becomes viscons and darker coloured. Analysis gave-I. 11. C ................ 81.35 81.55 H ................ 10.48 10.62 0 ............... 8-17 7.83 These numbers agree with a formula C40H6003 and this compound may be derived from the pyevious one by replacing two atoms of hydrogen with one of oxygen. The three constituents of the resin shorn a similar deportment towards reagents. The part soluble in ether and hot alcohol is alone attacked by melted pottash; the other two float on the potash as soft brown masses and are decom- posed with esca,pe of vapours of an aromatic odour.Concentrated sulphuric acid dissolves the three bodies on warming to brown liquids. A mixture of chromate of potash and sulphnric acid has no marked action upon any of them ; concentrated nitric acid has little action in the cold but when warmed with it on the water-batlh the three are converted into clew red liquids from which a part of tlie compounds ABSTRACTS OF CHEMICAL PAPERS. formed is precipitated on cooling and almost the whole on addition of water. These compounds are amorphous yellow masses containing nitrogen-probably nitro eompounds. This resin agrees in composition and properties with no other yet described. The one which comes nearest to it is from Settling Stones in Northumberland and con-sists according to Johnson of 85-29 C 11.03 H 3.68 0 and 3.25 ash.He assigned to it the formula C,H,,02 and supposed that it contained a hydrocarbon CIH,. The author is of opinion that it con-sisted of a mixture of different compounds. G. T.A. Petrified Wood of Lough Neagh. By Prof. HODGES (Chemical News xxx 102). AS the analyses of the petrified wood he had made did not satisfy Bischof that the wood had been petrified by t'he water of the lake but rather led to the inference that it resembled the silicified wood of the brown coal formations the author has made further analyses of the lake-water and finds that an imperial gallon of it cont,ains 12.95 grains of solid constituents consisting of 10.826 grains of mineral and saline matters of which 0.36 grains were silicic acid.The ash left after ignition of the wood was affected by the magnet as stated in the Phdosophical Transactions. The ash contained amongst other sub- stances 89.11 per cent. silicic acid and only *04 per cent. of iron oxide. The author therefore considers that the lapidifying material of the petrified wood is silicic acid and not oxide of iron. E. W. P. The Recent Eruption of Nisyros. By M. GORCEIX (Ann. Chim. Phys. [5] ii 333-354). PARTLY noticed already (see Journal 187'3 p. 1212 and 1874 pp. 347 562) but the complete paper contains a considerable amount of new matter and gives a connected view of the whole. The ''residue " obtained in the analysis of the gases from the fuma- roles b and c (p. 1212 of last volume) had the composition- Nitrogen.Marsh gas. Hydrogen ? 9S.2 5.9 0*9?= 100-0 The hot saline water discharged from the fissure which opened on June 8th 1873 collected in a small lake where as it evaporated it de-posited crusts of nearly pure sodium chloride. The water was slightly acid. It contained the following subst,aiices in 1litre :-Chlorine .......................... 113.00 Sulphuric acid .................... 1-06 Hydrogen sulphide ................ 0.01 Silica ............................ 0.07 Iodine ............................ traces Sodium .......................... 44.40 Calcium .......................... 16-60 0RGANIC CHEMISTRY. 49 Magnesium.. ...................... Potassium ........................ 2.73 1.72 Ferric oxide with a little alumina ....4.12 It is evidently sea-water highly concentrated and mixed with pro- ducts of the volcanic action. During the period of greatest activit,y the composition of the gases from the fumaroles was soniewhal altered the sulphuretted hydrogeii being diminished the total quantity of combuskible gases in the residue being increased and the hydrogen exceeding the marsh-gas in the pro- portion of 5.3 1. The immediate cause of the present eruption appears to have been the penetration of the sea-water into an ancient fissure which extends from Nisyros to the neighbouring island of Hyali its submarine course being indicated by an evolution of carbonic acid and sulphuretted hydrogen. The fumaroles which are all situated on thc line of this fracture usually afford sufficient vent for the vapour generated but for some time previous to 1871 a considerable diminution in their activity had been observed probably in consequence of accidental obstructions.The vapour thus acquiring a sufficient tension (which from the height of the column of water ejected the author calculates as at least 16 atmospheres) opened at first two small exits producing at the same time the phenomena of an incipient eruption. Succeeding upon this the sea-water penetrating with greater facility attained a greater depth and after some months produced a second eruption of still greater violence when part of the water was ejected in the liquid form still holding its salts in solution its organic matter decomposed by the high temperature appearing as marsh-gas and hydrogen. The author considers that the study of this eruption will throw light upon the causes of volcanic action in general X J. S.