940. Making Bread, and Obtaining Starch from the Materials employed Simultaneously. H. ANTHONISSEN, Brussels. Dated April 17, 1861. (Not proceeded with.)

For the purpose of making bread according to the instructions contained in the specification, a certain quantity of flour is mixed with cold water to make the dough, this is then transferred from the mixing trough to a washing apparatus of peculiar construction, provided with sieves and perforated diaphragms, in which by the action of a stream of water the starch may be partially removed from the gluten, falling through the meshes of the sieves, on the upper surface of which the constituent last mentioned and the coarser farinaceous particles are retained. The compact glutinous mass is then withdrawn, placed in contact with fermenting materials, and finally made into loaves of bread. The starch is collected from the washings by means of fine hair sieves, drained and dried.

The falsifications here proposed to be carried out in the manufacture of an important article of diet stands curiously in opposition to the common practice of mixing rice, potatoes, or other forms of starch with genuine wheaten flour before making into bread. Inasmuch as macaroni, semolina, &c., contain a considerable quantity of gluten and are well recognised nutritious articles of food, it cannot be positively asserted that evil consequences must follow as the result of any alteration in the relative proportions of starch and gluten in bread; but there are many circumstances which tend to show that a judicious combination of these constituents is easier of digestion than others which differ widely from the proportions usually found naturally associated in the common varieties of wheaten grain.

948. Increasing the Illuminating Power of Gas. H. CARSTANJEN, Cologne. Dated April 18, 1861. (Not proceeded with.)

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variety of confectionery products, using alcohol or water for extracting from the fruit the flavouring essence, and in some cases employing likewise the flowers.

Grants of Provisional Protection for Six Months.

2473. William Malam, Skinner Street, London, "Improvements in apparatus for the manufacture of gas."Petition recorded October 3, 1861.

་་

2986. Hermann Brambach, Lungengasse, Cologne, Germany, "A new mode of manufacturing gas for illuminating purposes."-Petition recorded November 27, 1861. 3103. William Clark, Chancery Lane, London, provements in stoppering bottles and other vessels."-A communication from M. Victor Hippolyte Solon, Boulevart St. Martin, Paris.-Petition recorded December

11, 1861.

Im

3208. William Mattieu Williams, Handsworth, Staffordshire, "An improvement or improvements in treating coal and other bituminous minerals and peat, in order to obtain solid and liquid hydro-carbons therefrom, and in apparatus to be used for that purpose."-Petitions recorded December 21, 1861.

"

3265. Thomas Pickford, Fenchurch Street, London, Improvements in the manufacture of manure.' 13. William Barker Patrick, Highgate, Middlesex, "Improvements in the manufacture of sugar, and in the apparatus employed therein."

23. Hermann Eschwege, Mincing Lane, London, “Improvements in treating wood and other vegetable spirit." -Petitions recorded January 2, 1862.

29. James Whitton Arundell, Gresham House, Old Broad Street, London, "An improved method and improved apparatus for removing impurities from coal, parts of which invention are applicable for the separation and cleansing of ore and other minerals."--A communication from Mr. Martin Neuerburg, Kalk, Rhenish Prussia.

37. Arthur Warner, Threadneedle Street, London, "Improvements in preparing materials for and in purifying coal gas."-Petitions recorded January 4, 1862.

55. John Stenhouse, Upper Brunswick Terrace, Barnsbury Road, London, "Improvements in rendering certain substances less pervious to air and liquids."

THE employment of benzine is here recommended as an agent suitable for the purpose of increasing the brilliancy of burning jets of coal gas; and an apparatus is described which consists of a small chamber through which the gas in its passage is made to take up a certain quantity of the vapourised material before being consumed at the burner. The agent here referred to is better known in this country under the name of benzol, and, employed in forms of apparatus very similar if not identical, has already been made the subject of many patent claims. 959. Electric Telegraph Apparatus. J. H. JOHNSON. coln's Inn Fields, London. A Communication. Dated April 18, 1861. (Not proceeded with.) This proposal refers to a modification in the arrangement of apparatus known as Morse's telegraph instrument, and consists in the employment of an electro-magnet, placed in circuit and traversed by the current of the line, and with its poles set in opposition with the contrary poles of the magnet in the ordinary Morse apparatus. The soft iron bar or armature usually provided is dispensed with under this arrangement.

3043. William Henry Balmain, St. Helen's, Lancashire, "Improvements in the manufacture of potash and salts of potash."-Petition recorded December 4, 1861.

2196. Patrick Robertson, Sun Court, Cornhill, London, of ammoniacal salts, and a substitute for animal charcoal." "Improvements in treating yeast, and in the manufacture Petition recorded September 3, 1861.

2229. Charles Felton Kirkman, Palace New Road, Lambeth, Surrey, "Improvements in obtaining manure from sewerage, and in the apparatus employed therein."

2238. Nicholas Doran Proby Maillard, Dublin, "Improvements in the material and preparation of the material and apparatus for making potash, pearlash, and caustic potash for commerce."

2800. William Albert Shepard, Pall Mall, London,

"Improvements in preparing and treating gutta-percha and india-rubber."-Petition recorded November 7, 1861. 2961. Alfred Vincent Newton, Chancery Lane, London, "An improved method of removing and preventing the formation of calcareous and saline deposits in steam boilers."-A communication from Lewis Baird, Cambridge, Massachusetts, U.S.-Petition recorded November 25, 1861. 2997. Henry Wilde, Manchester, "Improvements in magneto-electric telegraphs, and in apparatus connected therewith."-Petition recorded November 28, 1861.

tions to the Academy of Sciences and the Royal Society, and does not treat the Chemical to a réchauffé. The Society however, like a scientific Lazarus, has occasionally the opportunity of picking up some crumbs which fall from the great man's table.-I am, &c. F.C.S.

MISCELLANEOUS.

3225. Franço's Laurent and John Casthelaz, Rue St. Croix de la Bretonnerie, Paris, "Improvements in the manufacture of colouring matters."-Petition recorded December 24, 1861. 2288. Richard Waller, Baker Street, Portman Square, London, "Improvements in machinery and apparatus for manufacturing and refining cane juice and other saccharine

substances.'

2351. John Oliver, Colchester, William Sinnock, Sylvan Cottage, Woodford, Essex, John Grantham, Nicholas Lane, and Montague Richard Leverson, St. Helen's Place, London, "Improvement in the mode of obtaining certain chemical substances, and in the treatment of vegetable fibre, and in obtaining manurial and other products therefrom."-Petitions recorded September 20, 1861.

2377. Joseph Jacob, Golden Square, London, "Improvements in the mode of, and apparatus for, obtaining and treating hydrogen gas, and the application thereof to various purposes, parts of which improvements are applicable to the manufacture of iron and steel."-A communication from Carl Preisenhammer and Carl Weniger, Zöptau, Austria.-Petitions recorded September 23, 1861. 2597. Charles Denton Abel, Southampton Buildings, Chancery Lane, London, "Improvements in apparatus for the simultaneous manufacture of white lead and vinegar." -A communication from Robert Rowland, New York, U.S.-Petition recorded October 18, 1861.

3208. William Mattieu Williams, Handsworth, Staffordshire, "An improvement or improvements in treating coal and other bituminous minerals and peat, in order to obtain solid and liquid hydro-carbons therefrom, and in apparatus to be used for that purpose."

CORRESPONDENCE.

The Chemical Society.

To the Editor of the CHEMICAL NEWS. SIR,-"The authors shall not be at liberty to publish their Papers until they shall have appeared in the Transactions of the Society.' Such is the notice printed on the cover of the Journal of the Chemical Society, which contains papers read at the Society from Dr. Bolley and by Dr. Oppenheim. The communication from the former gentleman was published in Dingler's Journal, and copied into the Centralblatt, long before it was read at the Chemical Society; and that by the latter was read before the Chemical Society of Paris at their sitting on August 9 last, and was published in extenso in their Bulletin; an abstract also appeared in the Comptes-Rendus of the Academy of Sciences months ago. As a Fellow of the Chemical Society, I am, of course, obliged to any gentleman who sends papers; but after having read them in a foreign journal, I cannot help, when attending the meeting of our Society, having something of the feeling of a guest invited to a second day's dinner. I feel that the Society is to a certain extent snubbed. Our honoured and much-respected President manages better. He sends all his communica

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Transparency of Gold.-In describing the transrecent work, gives an illustration, which may be new to many of our readers :-"This transparency," he says, "may be elegantly demonstrated, by taking some twenty grains of fine gold, and fusing it in a convenient shallow vessel; this is to be removed from the furnace in a completely fluid state, when, if watched, it will be observed that just upon cooling a crust of solid metal will first suddenly form, through which the light of the internal red-hot mass appears of a beautiful brilliant green colour."

Calcining Sulphur Ores.-Some improvements in furnaces for calcir.ing sulphur ores, which are likely to become of importance in the manufacture of sulphuric acid, as they are said to offer a complete solution of the nuisance difficulty in the Swansea copper works, with the production annually of some 300,000l. to 350,000l. worth of sulphuric acid, at a merely nominal cost, have been invented by Mr. Peter Spence, of Pendleton. Alum Works, Manchester. The inventor has already five furnaces at work in his own business, and four licences just commencing. Taking Dr. Percy's data as his guide, he declares about half of the present expenditure of fuel, and with that he could undertake to calcine all copper ores with the conversion of all the sulphur eliminated into sulphuric acid, the only cost of this acid being the nitrate of soda, which, with his furnace, is only half of that regularly used; and, in addition to the interest of the capital invested in vitriol chambers, no labour would be expended on the acid manufacture.

The Adulteration of Bees'-wax by Japanese wax is detected, according to Hager, by their different behaviour in a concentrated solution of borax, at the boiling point. Bees'-wax is totally insoluble in such a solution, while Japanese wax dissolves, and on cooling forms a milky white, gelatinous mass. From a mixture of the two the latter is dissolved out, carrying with it a portion of the former, while another portion rises and congeals on the surface.

ANSWERS TO CORRESPONDENTS.

All Editorial Communications are to be addressed to the EDITOR; and Advertisements and Business Communications to the PUBLISHER at the Office, 1, Wine Office Court, Fleet Street, London, E.C.

Vol. IV. of the CHEMICAL NEWS, containing a copious Index, is now lettered. The cases for binding may be obtained at our Office, price ready, price 128., by post, 12s. 8d., handsomely bound in cloth, goldIs. 6d. Subscribers may have their copies bound for 2s. if sent to our Office, or, if accompanied by a cloth case, for 6d. A few copies of Vols. I. II. and III. can still be had. Vol. V. commenced on January 4, 1862, and will be complete in 26 numbers.

Pure Hydrogen.-A. A.-This may be prepared by passing the gas evolved from zinc and sulphuric acid, through a solution of caustic potash to absorb any free acid, then through a solution of nitrate of silver to absorb any arsenic or sulphur, and lastly through strong oil of vitriol, or over chloride of calcium to free it from moisture.

A. O. Z.-The best plan is to heat them; no other is effectual. The local action in your battery is most likely due to the solution of copper in the acid, and its subsequent precipitation on the zinc.

send an address where it will reach you. A would-be Fellow.-We will forward the desired information if you

SCIENTIFIC AND ANALYTICAL CHEMISTRY.

On Cryolite, by M. H. SAINTE-CLAIRE DEVILLE. SINCE the discovery and the exportation of an important deposit of this curious mineral on the sea coast of Greenland, important applications have been made of it. Dr. Percy, who first received some, extracted aluminium from it almost at the same time as M. H. Rose and myself, to whom M. Ho'mann sent some specimens of cryolite. It is now employed in the three aluminium manufactories, either as a flux or as a substance to be decomposed by sodium.

From its first introduction into Europe, it has been employed at Stettin, if I understand correctly, and certainly at Denmark, as a substance suitable for the preparation of soda and alumino-soda soaps. On that account it was first known in commerce under the name of soda mineral. The method employed in Denmark and Prussia, where it was utilised for the first time, consists in treating it with milk of lime at the boiling point of water. If the amount of lime is properly calculated, and the amount of water sufficient, the mixture is wholly transformed into fluoride of calcium and aluminate of soda. This reaction proceeds without attention and in a complete manner.

From this aluminate of soda a soap has been made which contains an enormous quantity of water owing to the alumina or the stearate of alumina which may be present. The aluminate has likewise been treated with gaseous carbonic acid, which converts it into carbonate of soda and a very dense aluminous precipitate, which was at first taken for alumina, but which, in reality, is

a carbonate of soda and alumina.

I have, indeed, received from Copenhagen, some years ago, a specimen of this alumina, which had been dried in the air or by a stove. It was very constant in com. position and appeared free from soda, since it had no taste. Its analysis yielded me the following numbers :— Alumina 44.8

Carbonate of soda
Carbonate of lime

Water and carbonic acid.

phosphoric acid, which I have not accurately estimated, on account of the invincible difficulty experienced in separating small quantities of phosphoric acid from an excess of alumina.

In the aluminium factory at Nanterre endeavours have chloride of aluminium and sodium, by mixing it with been made to employ this alumina to prepare the double salt and carbon; but it occasioned great surprise to find among the first products of the reaction of chlorine on the aluminous mixture a large quantity of phosphorus, which condensed and burned at the exterior part of the apparatus.

It is, therefore, seen that phosphorus exists in cryolite, and, unfortunately this element enters into all the products made from it, and always contaminates them in the aluminates of soda obtained from an aluminium an injurious manner. M. Persoz, who has examined factory at Rouen, has also proved the presence of phosphoric acid in it, according to a communication which he has kindly made to me. And, moreover, M. Morin and myself have each proved the presence of phosphorus in considerable quantity in aluminium made exclusively from cryolite and met with in commerce.

This is the process employed :-Dissolve the alumi nium in aqua regia containing an excess of nitric acid; evaporate the filtered solution in the presence of a great excess of nitric acid, and when the greater portion of the M. H. Rose's re-agent, that is to say, into molybdate acid is driven off pour the liquid, rather diluted, into of ammonia dissolved in nitric acid; heat it a little and estimate the proportion of phosphorus from the quantity of yellow phosphomolybdate precipitated, or from the colour of the liquid.

This is one of the numerous substances, together with marine salt, fluorides, silicium, and zinc, that must be sought for in commercial aluminium. For the details of the analysis I would refer to the small brochures which I have published upon this point; but I will take this opportunity to beg those numerous persons who have recently been devoting their attention to investigate the properties of aluminium to make an accurate analysis of the metal upon which they work. It is at present met with in commerce in very variable states of purity, and the discordant results which have been published respecting some of the reactions of aluminium may be due to the different and always injurious substances contained in it. Aluminium prepared from chloride of aluminium contains chiefly iron and chlorides derived from the flux. That which is prepared from cryolite, when this substance is exclusively used in the preparation of the metal, contains silicium, fluorides in rather large quantity, and, as has just been shown, phosphorus. Thus, the results obtained in researches must not be considered as being definitely settled until analysis has proved the purity of the material operated upon.

II. Analysis of Cryolite.-Berzelius has given the composition of cryolite, analysing it by means of

"De l'Aluminium." Mallet-Bachelier, Paris, 1859.

sulphuric acid. I have repeated his analysis and published numbers perfectly in accordance with his own. It was advisable to re-commence this analysis, employing the Danish method, that is to say, by means of lime, to estimate its value. This is how I proceeded, operating upon one gramme of powdered cryolite.

I added

I mixed it with the results of the calcination of 1059 grammes of perfectly pure carbonate of lime. a tolerably large quantity of water and boiled it, replacing the water in proportion as it disappeared by evaporation.

The filtered aluminate of soda was evaporated with an excess of nitric acid; the solid product was heated to 200° or 300° and extracted with water containing nitrate of ammonia and a little ammonia, which left behind a dense and nearly anhydrous alumina, which was calcined and weighed. The liquid containing the nitrates, from which traces of lime are precipitated, was evaporated and changed into carbonate by an excess of oxalic acid, a little tartaric acid, and calcination. The product, which was perfectly soluble and left no residue, was changed into chloride of sodium, which was weighed with the usual precautions. I thus obtained :

Aluminium Sodium

Fluorine (by difference)

:

These figures are the same as those obtained by the other method.

III. Vanadium.-To find the vanadium existing in small quantities in cryolite, I took fifty grammes, which I pulverised and fused with three times their weight of caustic potash and a few grammes of nitre. The mixture was pasty and almost liquid at a red heat, which could not be raised very high for fear of fusing the silver crucible employed. The mass, which was bluish-green, was poured into a cold silver dish: it was dissolved in water, which became of an intense green colour; there remained a slight crystalline and ochreous residue, which will be subsequently examined.

A few drops of alcohol precipitate the manganese and render the liquid colourless; it is then filtered and supersaturated with sulphuretted hydrogen. There is first obtained a slight brown coloration, due to an almost insensible deposit of sulphide of silver or lead; then there deposits cryolite, in the form of a pulverulent, transparent, and apparently gelatinous precipitate'; finally, the liquid assumes the red colour of sulpho vanadite of potash. Filter, treat with hydrochloric acid to almost exactly saturate the liquid, preserving a slight acid reaction. Heat, collect the heavy brown precipitate on a filter, roast the sulphide, fuse the vanadic acid and weigh it."

These fifty grammes of cryolite gave me fifty-five milligrammes of red oxide of manganese and nine milligrammes of vanadic acid. Sesquioxide of iron was found in the residue, insoluble in water, which was composed of unattacked cry olite, a little sesquioxide of iron, and, lastly, a little silver taken up by the potash from the crucible in which the fusion was effected.

On the Estimation of Tin, by M. H. ROSE. THE ordinary method of separating tin from the metals with which it is alloyed, and which consists in attacking it with nitric acid, may yield inaccurate results in the case of some metals the oxides of which are slightly mixture of oxides, these must be previously reduced by basic. If it is desired to employ this process for a hydrogen, an operation which can be readily effected in a small porcelain crucible.

It is known that another method consists in precipitating the oxide of tin (stannic acid) with sulphuric acid. This precipitation only takes place in dilute solutions when the oxide of tin is present in its a modification obtained by the decomposition of the bichloride. Care must be taken not to filter the precipitate, except after long standing, especially when the liquid contains hydrochloric acid; and in this case the whole of this acid must be well removed by washing; if any remains, there is a risk of losing some tin, which will be volatilised in the state of chloride at the moment

of calcination.

There is no advantage in replacing for the precipitation, as M. Löwenthal has done, the sulphuric acid by a sulphate, or by nitrate of ammonia.

Precipitation by sulphuric acid may lead to erroneous results when the solution contains bodies which are carried down by the oxide of tin and which cannot be extracted from the precipitate by hydrochloric acid. This is particularly the case with phosphoric acid.

If the tin exists in the state of alloy with other metals, it must be attacked with nitric acid as if the separation was to be effected by means of this acid. After the greater portion of the nitric acid has been driven off by evaporation in a porcelain capsule, the mass is moistened with rather concentrated hydrochloric acid, and the mixture left in contact for half-an-hour. Add a certain quantity of water, which dissolves the whole, and precipitate with sulphuric acid.

M. Reynoso proposed some time ago to estimate phosphoric acid by precipitating it with oxide of tin in a nitric solution. There must be employed, to remove the whole of the phosphoric acid from the liquid at least four or five equivalents of oxide of tin, and, if perfect security be desired, there should be eight or ten equivalents. The precipitate has not a constant composition.

The oxide of tin, when strongly calcined, only dissolves in traces in most acids. Concentrated sulphuric acid can dissolve it in the form of a thick syrup; but water precipitates all the oxide from the solution."

The calcined oxide is dissolved by sulphate of potash in fusion, but on dissolving in water all the oxide is seen to separate again.

Native oxide of tin (cassiterite) can only be attacked by fusion with alkalies.

Tin from Copper. -The ordinary method of separation by nitric acid furnishes for the oxide of tin a result a little too high, a small quantity of oxide of copper adhering to the oxide of tin. The method, which consists in dissolving the oxidised mass in hydrochloric acid, and precipitating the stannic acid with sulphuric acid, is more rigorous in this case.

The finely pulverised matter may also be fused with a mixture of sulphur and alkaline carbonate. Water dissolves, along with the sulphide of tin, an extremely minute quantity of sulphide of copper.

If the two metals are treated with a current of chlorine, the chloride of copper retains a trace of tin. Tin from Bismuth.-This cannot be effected by