NEWS

Researches on the Gases Dissolved in Molten Cast-Iron, Steel, and Wrought-Iron at Welding Heat.-L. Troost and P. Hautefeuille. The first instalment of a monograph treating on the nature and mode of absorption of gases (the same as those present in the reduction zone of the blast furnaces) by the metals alluded to when kept at high temperatures, and free from contact of air. In this portion of the essay, the authors particularly call attention to the gradual absorption of silicium by these metals, due to the action (corrosion) of the metals upon the silica of the crucibles-made of gaize, nearly pure silica, a mineral largely met with in France-when kept, viz., the metals in molten state, under strong pressure by means of oxide of carbon.

Combination of Sugar with Chloride of Potassium. - Ch. Violette.-Cane sugar forms with chloride of potassium a well-defined crystalline compound which is crystallographically described, while its chemical composition is C,H20KCIO; the formula of the sugar is, therefore, CHO, and the combination of sugar and chloride of sodium is C, H,NaCIO. This compound was discovered years ago by Peligot. The sucrate of chloride of potassium is not deliquescent. Solidification of Mixtures of Water and Acetic Acid.-E. Grimaux. This paper, illustrated by a diagram, treats on the point of congelation of mixtures of water and acetic acid in various proportions. The pure acid employed in these researches became solid at 144°, and contains, according to Rüderdorff's tables, 125 per cent of water. lengthy tabulated form containing the results of the experiments is added here. A mixture of 8379 water and 1621 acetic acid solidifies at 5°43°, the average of three determinations.

A

Sensitiveness of the Bunsen Gas-Burner Flame for Boracic Acid.-M. Bidaud.-The author minutely describes a series of results of experiments, from which it appears that when the flame is, without the use of blowpipe, brought near to a piece of porcelain whereon a minute crystal of boracic acid is placed, the flame is intensely greencoloured. Even with a solution only containing 9-10ths milligrm., of the acid the colouration is strongly marked. By accurate experiments the author ascertained that the colouration was not due to the combustion of the copper of the alloy (brass) of the tube from which the Яame issues.

Action of Zinc upon Chloride of Acetyl.-D. Tommassi and G. Quesneville.-After briefly referring to the late Gerhardt's researches on this subject, the authors state that they prepared the acetylide-as they call the result of the reaction alluded to-which is an amorphous, yellowish-brown coloured substance, soluble in alcohol, ether, chloroform, hydrochloric, fuming nitric, and anhydrous acetic acids, burning when ignited upon platinum foil with a bright flame. Dried at 100 and analysed, the composition of this body is found to be C16H1804. The reactions by which this body is formed are elucidated by a large number of complex formulæ.

Analysis of Agaricus Fætens. Dr. Sacc. This poisonous mushroom, gathered in dry weather in a forest under oak trees, was found to contain percentically-Water, 67 20; mannite, o 60; pectic acid, oog; fibrine, 4'66; bassorine, 155; woody fibre, 2009; fatty and colouring matter, o'68; ash, 5'13; total, 100'00.

Valuation of the Saccharine Matter in Beetroots.-E. Monnier. The author states that in order to ascertain the quantity of absolutely uncrystallisable sugar which beetroot will yield, it is required to estimate the ash (saline matter) very accurately, and to multiply the figure so obtained by 4 or 5, the latter being the highest coefficient,

Rendering Ladies' Dresses and other Wearing Apparel Unimflammable.-M. Trémaux.-The author advocates the use of mixtures of sulphate of potassa and alum in solution, to be concentrated according to the nature of the fabric it is intended to rendernot as is sometimes erroneously supposed incombustible, but uninflammable.

Berichte der Deutschen Chemischen Gesellschaft zu Berlin, No. 3, 1873.

Contains the following original memoirs and papers:

The Atomic Weight of the Cerium Metals, and on the Salts of the Protoperoxide (Ceroxydoxydul) of Cerium.C. Rammelsberg.-This monograph, elucidated by a large number of complex formula, treats on the composition of the salts of the protoperoxide of cerium, Ce,O,, but according to Mendelejeff (who takes the equivalents of cerium at 138, two-thirds more than the former equivalents, viz.,92) CeO2, while the protoxide of cerium then becomes Ce2O, formerly CeO. The salts alluded to are described at length, and the essay contains an exhaustive discussion on the atomic weights of the other metals of the ceriua group, viz., didymium, lanthanum, yttrium, &c.

Spontaneously Inflammable Phosphuretted Hydrogen Obtained from Iodphosphonium.-C. Rammelsberg.-The author briefly observes that the gas obtained from iod phosphonium by the action of caustic potassa is not spontaneously inflammable (see Ber. d. Deutsch. Chem. Gesells., 1871, p. 200), but becomes so while being evolved, and this is confirmed by an observation made by H. Rose (Pogg. Ann., 24, p. 345). ́

Sensitiveness for Light of the Haloid Salts of Silver when Developed (in Photographic Sense) by Alkalies.-H. Vogel.— The main features of this essay may be summarised as follows:-The photographic sensitiveness of the chloride. Bromide and iodide of silver is not simply affected by the intensity of the light, but is essentially modified by the method of development. For acid developers and white light the scale is-Iodide of silver>bromide of silver chloride of silver (the sign > signifies here "more sensitive than"). For alkaline developers-Bromide>chloride>iodide. With

coloured light (that is to say when violet and indigo are wanting) and alkaline developers the same scale holds good. For acid developers and dry plates the scale is iodobromide (iodbromsilber)>bromide> iodide of silver. With the wet process and acid developers the most sensitive mixture is (5Ag1+1AgBr); but with the dry process a mixture rich in bromide answers best. The method of preparation does not, according to my researches, affect the sensitiveness of the three haloid salts of silver alluded to.

Constitution of Hyperiodic Acid.-A. Basarow.-The contents of this memoir bear chiefly upon certain corrections which the author thinks are required to be made in Dr. Thomsen's essay on hyperiodic acid, recently published in Berichte der Deutschen, vol. vi., p. 2; and further we meet here with the author's theoretical views on the constitution of the acid.

The first

The Nitro Compounds of the Fatty Series (Fifth Part).V. Meyer and C. Wurster.--This essay is divided into the following sections:-Monobrom-nitroethan; dibrom-nitroethan. named is an oily liquid, boiling at from 145 to 1489 without decomposition; formula C,H,BrNO,. This body is acid, which forms with some of the alkalies crystalline salts, but in most instances a further decomposition sets in. The dibrom-nitroethan has not acid properties, is an oily fluid boiling at between 162° and 164°; the constitutional formula of the bodies alluded to are respectively

Contribution to our Knowledge on the Detection of Digitaline and Atropine.-H. Brunner.-Reserved for translation.

Conversion of Glycerine into Aceton.-O. Lange.-In the first part of this paper the author refers to the labours of Carius (Ann. Chem. Pharm., 155, p. 35) on this subject, and then relates at length the results of his experiments for converting crystalline dichlorbrom aceton into aceton by the action of granulated zinc and some sulphuric acid; the boiling-point of the aceton is 58°. This reaction, however, is very slow; it is elucidated by the following formula:

CH2Cl2Br2O+H10 C2H,Br+BrH+2C1H+H.O.

The aceton was, in order to ascertain its identity, combined with bisulphite of soda, the composition of that combination led to the formula CHO.SNaHOg.

A new Body of the Same Composition as Hydrocyanic Acid, -O. Lange. This essay records at length the results of an investigation of the slow reaction (continued for several months) of epichlorhydrine and hydrocyanic-anhydride placed together in equal parts in sealed tubes, and exposed to sunlight. After a lengthy process of purification, the author obtained a crystalline body, readily soluble in water and in boiling alcohol, but difficultly soluble in ether. When heated by itself it detonates, giving off a smell of hydrocyanic acid, while by being heated with water the substance is decomposed, depositing a humus-like substance. The formula of this new body is CNH; percentically, C, 4444; H, 3'70; N, 518.

The Systematic (Systematik) of Inorganic Chemistry.-L. Meyer.-Elucidated by a large number of formula and tables. This essay, bearing upon the theory of chemistry, is not suited for abstraction, notwithstanding its high intrinsic value.

Activity of Oxygen in the Processes of Slow Oxidation.-H. Fudakowski.-Reserved for translation.

Chloral and Acetonitrile.-H. Hübner.-After briefly referring to Bayer's researches on the reaction of chloral, benzol, and sulphuric acid, resulting in the formation of the compound C(CH3)2H.CCI, the author describes at length, and elucidates, by a series of complex formulæ, the results of his researches on the reaction between chloral and acetonitrile, whereby a peculiar amide of a bibasic chlorinated acid is obtained.

Action of Sulphocyanates upon Benzoic Acid.-A. Kekulé. This essay reviews chiefly the results of the researches on this subject obtained by Pfankuch (it is especially pointed out that the benzacrylic N.F., vol. xi., p. 97, does not exist), Kachler, Williams, Letts, Purper, acid obtained by this author, for which see Journ. f. Prakt. Chem.,

and others.

Action of Cyanide of Potassium upon Chloral, and on a New Method of Preparing Dichloracetic Acid.-O. Wallach.-At great length the author describes, first, the method of preparation of chloral-cyanhydrate, obtained by the action of 1 molecule of cyanide of potassium upon 1 molecule of chloral-hydrate in small quantity; while the reaction yields, in large quantity, dichloracetic acid ether, which, by treatment with HCl at 150° in a sealed tube, is readily converted into chlorethyl and dichloracetic acid, which may thus be readily prepared.

New Series of Aromatic Hydrocarbons.-Th. Zincke.-The third instalment of a monograph on this subject. This portion treats on the hydrocarbons formed by the action of zinc powder upon a mixture of benzol and benzyl-chloride.

On Griess's Phenylen-diamine, and on Bibrom-benzol.Th. Zincke and Fr. Sinteris.-The authors state, in the first place, that the brom-nitrobenzol, fusing at 38, may be readily converted into Griess's phenylen-diamine by first converting the aforesaid bromnitrobenzol into the thereto corresponding nitraniline, and next treating that with tin and hydrochloric acid. So obtained, the

Synthesis of Tyrosine.-A. Ladenburg.-Illustrated by woodcuts. Treats on Barth's experiments made with tyrosine, and on its rational formula, and on its synthetical preparation.

Constitution of the Chlorophenols, the Chloronitrophenols, and the Nitrophenols.-A. Faust.-Elucidated by lengthy and complex formulæ, as well as several tables. This memoir treats exhaustively on-Metachlorpara-nitrophenol, fusing-point 110°; metachlormeta-nitrophenol, fusion-point 70°; metachloroparanitrometa-nitrophenol, fusing at 110° to 111°; dimetachloropara-nitrophenol, fusing at 125°; parachlorometa-nitrophenol, fusing at 86° to 87°; parachlorodimeta-nitrophenol, fusing at 81°; parachlorometanitrometachlorophenol, fusing at 121° to 122°.

Action of Zinc upon Mixtures of the Aromatic Haloid Combinations and Aromatic Hydrocarbons.-Th. Zincke. Direct Formation of the Aromatic Amido-Derivatives.H. Salkowski.-The conclusion of an essay on this subject.

Les Mondes, February 27, 1873.

Crucibles of Great Resistance.-M. Lemagnent. - Without entering into particulars concerning the mode of manufacture, or the nature and properties of the ceramic paste of the crucibles supplied by the author, it appears that by practical experience these vessels are superior to any other, bearing as they do without any great deterioration, from 25 to 30 castings. The authorities of the French naval dockyard foundries speak in very high terms of these crucibles. Barometrical Table for the use of those who Ascend in Air-Balloons.-M. de Lagorge, C.E.-The tabulated form here published indicates for from 100 to 100 metres, viz., 100, 200, 300, and so on to 10,000, the reading of the barometer in millimetres corresponding to these altitudes. This table may readily also serve for determining the height of mountains.

Bulletin de la Societe d'Encouragement pour l'Industrie Nationale, No. 243, March, 1873.

Contains the following original papers relating to chemistry and collateral subjects:

Reports on the Ready-Made and Mixed Vitrifiable Pigments for Staining Glass and Porcelain, as Prepared by Lacroix.-J. Salvetat.-The contents of this paper relate to the mode of preparation of the mineral pigments used in staining glass and porcelain, and mixed ready for immediate use, being preserved in tin tubes akin to those used for artists' colours.

Presence of Phosphorus (Phosphoric Acid) in the Ashes of Coals and Coke.-Le Chatelier and L. Durand Claye.-The contents of this paper, elucidated by numerous quotations of results of analysis of coal-ash published in various treatises on metallurgy and on geology and chemistry, bear more particularly upon the fact that by the presence of phosphoric acid, which varies in quantity from 0'20 to even 3'01 per cent, in coal-ash, phosphorus is introduced into crude cast-iron, as well as into the iron castings made in foundries.

The Great Salt- Mines of Poland; and the Gypsum-, Sulphur-, and Petroleum-Bearing Strata of that Country and Galicia. -E. Heurteau.-The first instalment of an exhaustive report on these matters as the result of a lengthy visit to the localities alluded to.

Although not belonging to chemistry attention is called to the following memoir :

Report on Donnet's Improved Machinery for Forcing into the Soil the Iron Tubes used for the So-called Norton or Tube Wells.-M. Tresca.-Illustrated with engravings.

PATENTS.

March 7, 1873.

505. H. Deacon, Widnes, Lancashire, "Improvements in the manufacture of chlorine."-Petitions recorded February 11, 1873.

511. S. W. Maquay, Dublin, "An improved process to be employed in the manufacture of manures, and machinery or apparatus therefor." 513. H. Campbell, Queen Anne Street, Middlesex, "Improvements in the manufacture of manure, and apparatus therefor."-Petitions recorded February 12, 1873.

539. J. Noad, Hackney Wick, Middlesex, "Improvements in the manufacture of sulphurated lead, in apparatus therefor, and in its application to various useful purposes."-Petition recorded February 13, 1873.

547. J. G. Willans, Bayswater, Middlesex, "Improvements in the manufacture of iron and steel."

Middlesex, "An improved composition for removing and preventing 551. D. Hutchison, Mile End, and W. G. Bridges, Stepney, incrustation in boilers."-Petitions recorded February 14, 1873.

562. T. A. Rochussen, King William Street, London, " Improvements in the manufacture of iron and steel, and in apparatus employed therein."-A communication from R. Daelen, Neuss, 567. R. Cockshott, Bradford, Yorkshire, "A new or improved oil or lubricant."

Germany.

569. J. Patison, Airdrie, Lanarkshire, N.B., "Improvements in the destructive distillation of coal and shale for the production of illuminating gas, fuel, and oil, and other products therefrom, and in the apparatus therefor."

570. H. Y. D. Scott, C.B., Ealing, Middlesex, "Improvements in the deodorisation of excreta, and in the manufacture of manures therefrom."-Petitions recorded February 15, 1873.

588. A. J. H. Hutchings, Bristol, Improvements in spicing and preparing malt or distilled vinegar, rendering the same better suited for pickling purposes."-Petition recorded February 17, 1873.

599. C. W. Sutton, Stowmarket, Suffolk, "Improved combinations of ingredients for removing acidity from ales, beers, porters, wines, &c., and also to preserve them from acidity."

607. G. Noble, Woodford Bridge, Essex, "An improved method of treating fibrous materials for the manufacture of pulp for paper."— Petitions recorded February 18, 1873.

642. W. G. Martin and R. E. R. Martin, Hemingstone Hall, Suffolk, "Improvements in the manufacture of artificial fuel."-Petition recorded February 20, 1873.

NOTICES TO PROCEED.

3040. P. Maccallum, Dunfermline, N.B., "A new or improved artificial fuel."-Petition recorded October 15, 1872.

3142. A. V. Newton, Chancery Lane, Middlesex, "Improvements in furnaces for burning sulphurous ores."-A communication from K. Walter, Augsburg, Bavaria.-Petition recorded October 23, 1872.

3194. T. Colby, Dunstable, Bedfordshire, and J. E. Poynter, Glasgow, N.B., " Improvements in obtaining caustic baryta."-Petition recorded October 28, 1872.

3412. G. Alsing, Preston, Lancashire, "Certain improvements in the treatment of night-soil and other refuse matter."-Petition recorded November 15, 1872.

274. R. H. Patterson, Hammersmith, Middlesex, "Improvements in the purification cf coal-gas, and in the production of alkaline sulphides to be employed for such purpose."-Petition recorded January 23, 1873.

370. J. Richardson and J. Watson, Gateshead-upon-Tyne, Durham, "Improvements in puddling and rolling-mill furnaces."-Petition recorded January 30, 1873.

429. J.P. Sharp, Birmingham, "Improvements in the manufacture of steel, and in case-hardening, or partially converting iron into steel." -Petition recorded February 5, 1873.

458. A. Lafargue, Westbourne Park, Middlesex, "Improvements in the production of gas or vapour from hydrocarbon oils or combinations thereof with other matters, and in means or apparatus employed in utilising the same."-Petition recorded February 7, 1873.

PATENTS SEALED.

2573. J. Hargreaves and T. Robinson, Widnes, Lancashire, "Improvements in the manufacture of hydrochloric acid, and in apparatus employed therein."-Dated August 29, 1872.

2596. J. Hargreaves and T. Robinson, Widnes, Lancashire, "Improvements in the manufacture of salt."-Dated August 31, 1872.

2630. J. W. Pollard, Mincing Lane, J. Schofield, Mark Lane, and A. Butel, Merchant Street, Bow, Middlesex, "Improvements in the treatment of spent oxides of iron for the purpose of extracting cyanides."-Dated September 4, 1872.

2649. W. Meister, E. Lucius, and A. Brüning, Hoechst, near Frankfort-on-the-Main, Germany, "Improvements in the manufacture of colouring matter suitable for dyeing and printing."-Dated September 6, 1872.

2790. R. Stone, Liverpool, "An improved artificial fuel."-Dated September 28, 1872.

2801. J. McDougall, Manchester, "Improvements in the manufacture of manures."-Dated September 21, 1872.

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NEWS

SINCE the elaborate experiments of Deville and Troost on the vapour-densities of substances at high temperatures, little has been added to chemical science in this field of research. Doubtless this is in great part owing to the difficulty of any one student manipulating the complex apparatus necessary for the execution of the experiments. But the operations are greatly increased in difficulty, when we select bodies that are readily inflammable in air and attack with facility glass and porcelain at the high temperatures to which they are exposed. This is the reason why the molecular weights of a most important class of elementary bodies, viz., the Alkali-metals (although these are volatile at moderate temperatures), have remained to the present time undetermined. It was with the view of adding something to our knowledge in this department that we recently undertook some experiments with potassium, the results of which we now beg leave to lay before the Society. The special difficulties we had to overcome are involved in the endeavour to answer the following questions:

1. Is it possible to convert potassium into a gas of one atmosphere's pressure at any of the constant temperatures we can at present command?

2. Is it possible to generate pure potassium-vapour, and to keep it from getting oxidised?

3. Supposing a definite volume of such vapour to have been procured, how can its weight be ascertained? After a succession of failures, which we shall not detail,

we at last succeeded in devising a workable process, which

may be briefly described as follows:

A cylindrical iron bottle, of at least 200 c.c. capacity, of a thickness in the body ensuring sufficient rigidity at even a bright red-heat, and provided with a well-ground inbent neck, pierced with a canal of about 2 m.m. in diameter, is employed as a generator and receptacle of the

vapour.

* A Paper read before the Royal Society.

ground-in wire plug, at once immersed into a mass of

potassium ceases, the nozzle is closed by means of a

mercury, contained in a test-tube, and the bottle withdrawn to a proper support, on which it is allowed to cool.

After it has reached a manageable temperature, the bottle is inserted into a mass of recently boiled water, the wire plug withdrawn, and the hydrogen formed by the action of the water on the potassium pumped out by means of a "Sprengel" into a eudiometer, to be measured.

In the experiments we have hitherto carried out, we have satisfied ourselves that the amount of mercury vapour not swept out by the potassium is quite inappreciable; and as our object has been in the meantime to merely arrive at approximate results, and to perfect our methods of manipulation, we have neglected the minute correction which-on account of that small remnant of mercuryought, strictly speaking, to have been applied to the volume of the vapour as calculated from the capacity of the bottle in the cold, the coefficient of expansion of iron, and the temperature (1040° Deville) at which the vapour was measured.

The results of our observations conclusively show that the density of potassium vapour, as produced in the process described, cannot exceed 45 times that of hydrogen, and that therefore the molecule of potassium consists of two atoms (K2).

We intend to prosecute our research in other directions, proposing to ascertain, if possible, the densities of the iodides of cæsium, rubidium, and potassium, these being, according to Bunsen's experiments, the most volatile of the haloids of the alkali-metals.

SEPARATING GOLD FROM ARGENTIC CHLORIDE.*

By ADOLPH LEIBIUS, Esq., Ph.D., Senior Assayer of the Sydney Branch of the Royal Mint.

IN refining argentiferous gold by means of chlorine gas (Miller's patent), the silver is eliminated in the form of chloride of silver, or, as now termed, argentic chloride. In the paper read by Mr. Miller before this Society, on that I need not refer to more of it than that part which December ist, 1869, he described this process so fully speaks of the argentic chloride produced. This argentic chloride is never pure, but contains, besides chloride of copper, a considerable quantity of gold, stated by Miller, in the paper quoted above, as 2 per cent of the gold previously refined. If this auriferous argentic chloride is reduced to metallic state without freeing it of its gold, silver bullion results, containing from 12 to 20 per cent of gold, the average being about 18 per cent. This gold exists chiefly in combination with chlorine, and also as a double compound of chloride of gold and silver. By melting the chlorides in a boraxed clay pot, with from 8 to 10 per cent of metallic silver, the greatest part of this gold was removed, but never the whole. Miller states that, with proper care, the amount of gold remaining in the silver need not exceed 3 parts in 10,oco. While such was ments were going on, the amount of gold left in the silver the case in many instances during the time the experithe average being 13 parts in 10,000. Lengthy experience bullion produced varied from 3 to 27 parts in 10,000, obtained since has shown that, when working on a large scale, and therefore with less time at disposal than when engaged in experimental trials only, the results became still more variable, the gold in the silver bullion having been not seldom as much as 100 to 150 parts in 10,000, and often 10 to 40 parts in 10,000. This irregularity in the results obtained made it desirable to institute further experiments with a view of arriving at a method which

* Read before the Royal Society of New South Wales, Novem ber 20th, 1872.