Palæopicrite of Amelose and the Products of its Alteration. By R. BRAUNS (Jahrb. f. Min., 5, Beilage, 275-329).-Since 1831, when Breithaupt first showed that the well-known crystals found at Snarum, Norway, were pseudomorphs of serpentine after olivine, the alteration of olivine and the new minerals formed thereby have frequently been the objects of careful investigation. In no place, however, is the immediate connection of olivine with the products of its alteration so apparent as at Amelose, near Biendenkopf, in Hesse, where within an area of a hundred square yards is found not only the olivine rock in place, but also all the recent minerals formed from it. The latter include serpentine, chrysotile, metaxite, picrolite, a new magnesium iron silicate, calcite, and quartzite interesting_on account of the occurrence of the extremely rare planes R, R. The matrix of these minerals differs from that of most serpentines in that it is of Devonian age, aud not interstratified in crystalline schists. It is, in fact, an olivine-diabase (palæopicrite). The new mineral is named by the author webskyite, after the late Professor Websky of Berlin. It is amorphous, and has a pitch-black colour with a brownish-green streak. In thin fragments, the colour is bright green. The hardness is 3, and the sp. gr. only 1.771. Its constituents are qualitatively the same as those of serpentine. Its quantitative composition, however, is different, since it contains 31 per cent. of water, 21 per cent. of which is lost at 100°. Analysis shows that the mineral has the formula H.R.Si,О13 + 6H2O, in which R represents Mg and Fe. The new mineral is probably of more frequent occurrence than might be imagined; the author having discovered it on specimens of diopside and of serpentine in the Berlin and Marburg museums. B. H. B. A Variety of Granulite, the Matrix of two New Minerals. By H. SAUER (Jahrb. f. Min., 1887, ii, Ref., 295; from Zeit. deutsch. geol. Ges., 38, 704-706).—In a new quarry by the railway station of Waldheim in Saxony, the following two new minerals were found in the granulite :-Prismatine, crystallising in rhombic prisms without terminal planes, grouped radially. It resembles andalusite or sillimanite. Its composition is given under I. It easily alters to a finely fibrous substance, termed cryptotile (Analysis II): SiO2. Al2O3. FeO. MgO. NagO. K2O. H2O. Total. 99.50 7.70 99.89 B. H. B. Rocks from the Congo. By C. KLEMENT (Jahrb. f. Min., 1887, ii, Ref., 300-301; from Tschermak Min. Mitth., 8, 1-27).-The author gives analyses of two specimens of laterite from the Congo. They are composed of a conglomerate of quartz grains cemented by a brown to yellowish-red material. The red rock (I) is more porous than the brown (II), and seems to be a product of the decomposition of the latter. These laterites are said to be a detritus of the crystalline schists in the interior of the continent. For the analyses, the material was freed from the coarsest quartz grains. The Water Supply of Oderzo. By M. SPICA and G. HALAGIAN (Gazzetta, 17, 317–323).—The water supply of the municipality of Oderzo is taken from three mountain springs, Monticano, Lia, and Navisego, which pass through a clay soil. The analyses tabulated below show that these waters are of the highest order of purity. The colour viewed through a tube was a pale-yellow. With an alcoholic solution of tannin (Hager's test), they remained perfectly clear for several days. With phenolphthalein, they showed no reaction, but with litmus they appeared slightly alkaline. Results of Analyses expressed in grams per litre. Arrangement in Space of the Atoms in the Molecules of Carbon-compounds. By J. WISLICENUS (Chem. Centr., 1887, 1005 -1009).-Van't Hoff and Le Bel were the first to explain the optical difference of certain carbon-compounds by a difference in the relative arrangement of the atoms in space within the molecule; since their work, however, no serious attempt has been made to apply their theory to explain the isomerism of certain compounds, whose composition, according to present views, is identical. Such peculiar cases as those established by the researches of Fittig on the isomerism of maleïc and fumaric acids, however, and the discovery of a third and fourth monobromocinnamic acid, have been classified under the generic term of alloisomerism. Chemists hitherto seem to have contented themselves with a name. Adopting the hypothesis of van't Hoff and Le Bel that the atoms occupy the solid angles of a tetrahedron, being arranged around a central carbon-atom it is evident that two carbon-atoms, associated together in the paraffinoïd form of combination, would revolve around one common axis, passing through the point of union of the atoms and the direction of attraction of two associated atoms, such as those of hydrogen. When two carbon-atoms are combined together, as in the olefines, they can only revolve round an axis which is the straight line connecting the two common carbon-atoms. Supposing all four of the affinities of the saturating atoms are unequal, then six isomerides are possible, in the case of two pairs three isomerides, and three also if two affinities are equal and two unequal. For maleïc acid, van't Hoff has proposed the formula CH-COOH In order to explain the conversion of maleïc into fumaric acid through the intervention of halogen-derivatives of succinic acid, it is supposed that the atoms combined with neighbouring carbon-atoms mutually react on one another according to their chemical affinity. Hence, it follows that two carbon-atoms combined together by one affinity, and being in a position by revolution around their axis to give way to this attraction, will so arrange themselves that the associated radicles interchange positions in the system. Such a relative arrangement will be stable in the cold, but at a higher temperature, as the interoscillation of the elements will be more frequent, there is a loosening of the affinities, and a different configuration ensues. When an unsaturated compound passes into one that is saturated, it is indifferent to which of the two carbon-atoms each particular radicle attaches itself; the compounds formed are identical. But if an atom is combined with two different radicles, then by addition an asymmetrical carbon-atom results according as the added atoms attach themselves to one or other position of affinity. This explains the formation of optically inactive compounds under these conditions, since both modifications are produced in equal quantities. As regards the nomenclature of these different geometrically isomeric configurations, it is proposed to call the arrangement ась bCa aCb the centrally or axially symmetrical, and the arrangement || the plane symmetrical. a Cb The following examples are given in illustration of the above views:-Tolane dichloride exists in two modifications; according to the author's hypothesis, the modification of higher melting point, obtained by the direct chlorination of tolane, is the plane symmetrical Ph.C.Cl Ph.C.Cl , whilst the other is the axially symmetrical || . As Ph.C.CI Cl.C.Ph fumaric acid is principally formed by heating malic acid, in which, doubtless, the carboxyl-group has more inclination towards the hydrogen-atom than to the hydroxyl- or other carboxyl-group, its COOH-CH-OH constitution may be represented by a configuration HH.C.COOH from which by the abstraction of a molecule of water the formula COOH-CH || results. The conversion of ethyl maleate into ethyl HC-COOH fumarate by iodine is explained by the intermediate formation of diiodosuccinnic acid, an interchange of position of the iodine- and hydrogen-atoms; the removal of a molecule of hydrogen iodide gives ethyl iodofumarate, which in its turn is reduced by the hydrogen iodide to ethyl fumarate. The reverse process of conversion of fumaric into maleïc acid through the intervention of dibromosuccinic acid can be explained in like manner. The isomerism of crotonic and isocrotonic acid is also of a similar order, the constitution of the one being expressible by a should also exist in two geometrically isomeric forms, of which, as yet, only one has been obtained. B-Coumaric acid has the plane symmetrical arrangement as it is easily converted into its lactone, coumarin; in its isomeride, the atoms are arranged in the axially symmetrical configuration; this, by fuming hydrobromic acid, is converted into coumarin, by temporary addition of a molecule of the acid, and by an inclination towards formation of the lactone. By this theory, the removal of the elements of a halogen acid and simultaneously of carbonic anhydride from the sodium salt of a B-halogen substituted acid is explained, as also the formation of anhydrides and lactones when two carboxyl- or a hydroxyl- and carboxyl-group are in the y-position. The author is engaged on experimental evidence in favour of this theory. V. H. V. Nitrosates, Nitrosites, and their Derivatives. By O. WALLACH (Annalen, 241, 288-315).-The crystalline compound which Guthrie. (Annalen, 116, 248; 119, 84) obtained by the direct union of amylene with nitrogen peroxide, is most conveniently prepared by passing the nitrous fumes evolved by the action of strong nitric acid on arsenious oxide into a well-cooled mixture of amylene (1 vol.) and glacial acetic acid (2 vols.). The operation is interrupted when the colour of the liquid changes from blue to green. The crystals are washed with acetic acid, afterwards with water. As commercial amylene is a mixture, the product is not homogeneous. On recrystallisation from chloroform or benzene, two substances having the composition CsH10N2O, are deposited, namely, cubes melting at 96-97°, and needles melting at 89°. This compound is not a dinitrite but a nitroso-nitrate or nitrosate. On boiling with alcohol and aniline, it yields aniline nitrate and amylenenitrolaniline, NHPh C, H, NOH. The base melts at 140-141°. It dissolves freely in ether, chloroform, warm alcohol, and in dilute acids, and crystallises well. The hydrochloride, CH16N2O,HCl, is deposited from a hot aqueous solution in anhydrous crystals. It is best prepared by passing hydrogen chloride into an ethereal solution of the base, when the hydrochloride is precipitated in the form of a crystalline powder. The nitroso-compound, NO NPh C,H,NOH, is deposited as a crystalline powder when a solution of sodium nitrite is poured into an acid solution of the base. It melts at 127-128°, and is soluble in alcohol and in alkalis. The nitroso-compound is reprecipitated on adding an acid to the alkaline solution. The hydrochloride is decomposed by boiling with water, or better with hydrochloric acid, yielding hydroxylamine and a ketone base, NHPh C,H,:0. The new base melts at 61°, and is soluble in alcohol, ether, and in hot water. Amylenenitrolparatoluidine, C12HN2O, and its hydrochloride and nitrate form well-developed crystals. The base melts at 111-112°, and the nitroso-derivative at 147-148°. The hydrochloride is decomposed on boiling it with hydrochloric acid, yielding hydroxylamine and the base C12HIN2O melting at 98°. Amylenenitrolorthotoluidine melts at 115°. The nitroso-derivative melts with decomposition at 149-150°. The hydrochloride is more soluble in water than the corresponding para-salt. Amylenenitrolorthoanisidine melts at 138-139°. The hydrochloride is deposited from its aqueous solution in prisms. Amylene nitrosate and piperidine act on each other very energetically, forming a crystalline base, C10H20N2O. It melts at 95-96°, and is insoluble in water and in alkalis. The salts dissolve freely in water. The hydrochloride is an oily liquid, but the platinochloride (CH20N2O)2, H2PtClε, forms beautiful prisms. Amylenenitroldiethylamine crystallises in plates and melts at 71-72°. Amylenenitrolallylamine is soluble in water. The hydrochloride, CH16N2O,HCl, is crystalline. This base is isomeric with nitrosoconiine. Amylene nitrosate acts on sodium ethoxide, forming a crystalline compound which melts at 100°, and also on ethyl acetoacetate, yielding a crystalline compound of the composition CHINO CH(COMe)·COOEt. Guthrie (loc. cit.) observed that amyl nitrosate acts on potassium |