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suming 33 feet of coal-gas per hour, is capable of melting
8 oz. of copper and 6 oz. of cast iron; that the next sized
furnace, consuming about twice the quantity of gas, will
melt 40 oz. of copper.

Mr. Siemen's furnaces, I am happy to say, are not in a state of mere experiment, but they have received the sanction of a great number of manufacturers, and especially of those who little expected that the necessary heat for their But the most important improvement which has been operations could be obtained without interfering with their effected of late years in the production of intense heat by manufacture, in the carrying out of which they thought the combustion of the gases generated through the dis- the production of smoke could not be prevented. Thus, tillation of inferior coals is that of Mr. C. W. Siemens, we find M. Siemen's furnaces employed with great success F.R.S., of Great George Street. The benefits which are and economy in glass works, in potteries, and in iron forges, conferred on manufacturers and the public by the furnaces-works which used to be a nuisance to their neighbours, devised by Mr. Siemens cannot be overrated. They are not only economical in their use, but, as they enable the manufacturer to use an inferior class of fuel to generate the heat required, they must undeniably be of great advantage; and to the public in general they will be a great boon, as they do away with the nuisance attached to all manufacturing districts in the dark black smoke escaping from chimneys, polluting the atmosphere, and rendering it so disagreeable to those who are compelled by their occupations to live within reach of its influence.

I may state, en passant, that the large amount of black smoke which floats in the atmosphere of Manchester, Sheffield, Birmingham, and other towns, is not only injurious by depriving those places of much light,-so beneficial to life and health-but is also a nuisance from the immense amount of soot and dirt with which it is accompanied. There cannot be a doubt that, owing to the imperfect combustion which the products undergo in many of the furnaces belonging to manufacturers, and which is shown by the appearance of the smoke itself, the air is rendered more unwholesome than it would be if the products that escape had undergone perfect combustion, because volatile matters escape which are known to have a most destructive action on health and vegetation. The improved state of the public squares in London, and especially of those which are on the banks of the Thames, can be witnessed by all who have observed their condition since the consumption of smoke has been made compulsory in London and its suburbs.

by the large volumes of black smoke which they were constantly emitting from their chimneys.

Before describing Mr. Siemen's furnace, it is necessary that I should state that, in the ordinary furnaces, only about 25 per cent. of the heating power of the fuel is rendered available in carrying out the manufacturing operations. This is due to imperfect combustion, and to the fact that only the heat of combustion exceeding that of the body treated is utilised; the remainder of the heat, in many instances, by far the greater proportion of the whole, being allowed to escape uselessly up the chimney. I shall now give a description of one of M. Siemen's furnaces. The gas-producer and furnace are quite distinct, and may be placed at any convenient distance from each other. The gas-producer is shown in Fig. 1. The fuel is supplied, at intervals of about two hours, through the covered openings A, and descends gradually on the inclined plane B, which is set at an inclination to suit the kind of fuel used. The upper portion of the incline B is made FIG. 1.

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-The fuel, descending slowly on the incline plane B, becomes heated, and parts with its volatile constituents, the hydrocarbon gases, water, ammonia, and a small proportion of carbonic acid-which are the same as would be evolved from it in a gas retort. There now remains from 60 to 70 per cent. of purely carbonaceous matter to be dis posed of, which is accomplished by the current of air slowly entering through the grate C, producing regular combustion immediately upon the grate; but the carbonic acid (an incombustible gas) thus produced having to pass slowly through a layer of incandescent fuel from two to

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three feet thick, takes up another equivalent of carbon, and is thus transformed into carbonic oxide (an inflammable gas), which passes off with the other combustible gases to the furnaces. For every cubic foot of carbonic oxide thus produced, taking the atmosphere to consist of one-fifth part by volume of oxygen, and four-fifths of nitrogen, two cubic feet of incombustible nitrogen pass also through the grate, tending greatly to diminish the richness or heating power of the gas. Not all the carbonaceous portion of the fuel is, however, volatilised on such disadvantageous terms; for water is brought to the foot of

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the grate by the pipe E, which, absorbing the spare heat from the fire, is converted into steam, and each cubic foot of steam, in traversing the layer of from two to three feet of incandescent fuel, is decomposed into a mixture consisting of one cubic foot of hydrogen, and nearly an equal volume of carbonic oxide, with a variable small proportion of carbonic acid. Thus, one cubic foot of steam yields as much inflammable

gas as five cubic feet of atmospheric air; but the one operation is dependent upon the other, inasmuch

as the passage of air through the fire is attended with the generation of heat, whereas the production of the water gases, as well as the evolution of the hydrocarbons, is carried on at the expense of heat. The generation of steam from the water, being dependent on the amount of heat in the fire, regulates itself naturally to the requirements; and the total production of combustible gases varies with the admission of air; and since the admission of air into the grate depends in its turn upon the withdrawal of the gases evolved in the producer, the production of the combustible gases is entirely regulated by the demand for them.

The gas made in these producers has been frequently carefully analysed, and the average constituents of 100 parts have been found as follows:Carbonic acid . • 4'I Oxygen.

Carbonic oxide.

The furnaces are applicable for all purposes where intense heat is required, such as for glasshouses, puddling, heating

NEWS

iron and steel, iron melting for foundry purposes, steel melting, muffles and copper smelting. In all applications the furnaces are of the same construction in principle, the arrangements only varying with the different operations to be carried on in the heating chamber. The heating furnace has been selected for illustration in Fig. 2. Underneath the heating chamber K are placed transversely the four regenerators L L L L, which are chambers filled with fire-bricks built up with spaces between them. The regenerators work in pairs, the two under the righthand end of the furnace communicating with that end of the heating chamber, while the other two communicate with the opposite end.

The gas passes from the main gas flue through the reversing valve S into the flues R R, at the bottom of one of the regenerators L, up through which it passes to the port M. Air is also admitted through a reversing valve at the back of S (not shown in the figure), thence into the flues O O, up through the second regenerator L, to the port N, where it meets with the gas, mingles with it, and produces an intense and uniform flame, which distributes itself all over the heating chamber K.

The products of combustion together with the excess or waste heat of the furnace, instead of being passed, as in ordinary furnaces, up the stack, and either entirely thrown away or only partly utilised, are carried down into the other pair of regenerators, where they are deprived of their heat, and thence proceed through the reversing valves to the chimney by the flue T.

When one pair of regenerators has become considerably heated by the passage of the hot products of combustion for some time, and the opposite pair correspondingly cooled by the upward passage of the cold gas and air, the valves are reversed, and the currents of gas and air then pass upwards through the regenerators last heated, whereas the products of combustion pass through those opposite. The process of reversing is repeated at fixed intervals, generally every half hour, so that two of the regenerators are always being cooled by the gas and air taking up the deposited heat and carrying it back to the furnace, and two always being heated by the passage of the hot products of combustion passing down to the chimney, and depositing their heat on their way there.

The flame in the heating chamber is uniform throughout, and perfectly free from all extraneous matter. Its chemical nature is also perfectly under command by means of gas and air regulating valves (not shown in the engravings), so that the most delicate operations can be carried on with great uniformity.

by using inferior qualities, such as coal and coke dust, lignite, and peat.

The intensity of the heat, purity of the flame, and the absence of cutting draughts in the heating chamber, is of great advantage for all metallurgical operations, tending greatly to improve the quality of the produce, and occasioning a saving of about 5 per cent. in the waste of the metal treated in puddling and iron re-heating furnaces, &c.

The peculiarities and advantages of these furnaces are, that gas fuel alone is employed, that perfect and entire combustion is obtained, and that the heat, which is usually allowed to escape up the chimney, is here stored up to be afterwards brought back to the furnaces.

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Professor W. A. MILLER, M.D., F.R.S., President,
in the Chair.

BEFORE proceeding to the ordinary business of the even-
ing, the PRESIDENT, pursuant to notice, reminded the
Society that it had been proposed to entertain suggestions
having reference to the disposal of some chemical speci-
mens and products which had from time to time been
presented to the Society, but were even now far from
being a complete collection. Their number amounted to
more than could be conveniently accommodated in the
glass cases of the adjoining library, and their importance
did not warrant an expenditure for their proper display;
but, inasmuch as the Council did not feel themselves
justified in disposing of them without the sanction of the
Fellows being first obtained, he was instructed by his
colleagues in the Council to say that they would be pre-
pared to act upon any suggestion which met the wishes
of the meeting. Dr. Miller concluded by reading an
extract from the Royal Charter to the following effect :-
"And we further will, grant, and declare, that the whole
property of the said body politic and corporate shall be
vested, and we do hereby vest the same solely and abso-
lutely in the Fellows thereof, and that they shall have full
power and authority to sell, alienate, charge, and other-
wise dispose of the same as they shall think proper; but
that no sale, mortgage, incumbrance, or other disposition
of any messuages, lands, tenements, or hereditaments
belonging to the said body politic and corporate shall be
made except with the approbation and concurrence of a

It was then proposed by Dr. GLADSTONE, and seconded by Mr. MAKINS, "that authority be given to the Council to dispose of the chemical specimens in any manner which may seem to them fit."

The gas and air reach the heating chamber (after pass-general meeting." ing through the regenerators) at nearly the heat of that chamber itself, and in burning, in addition to the temperature due to their mutual chemical action, is added that they have taken up in passing through the regenerators, so that an intensity of heat is obtained, which, unless moderated on purpose, would fuze furnace and all exposed to its action.

Professor CHURCH protested against the dispersion of the Society's Museum, which, although now but small, might become the nucleus of a larger and more important collection. He considered that the donation of specimens should be encouraged, for he had himself derived benefit from their inspection, and had on more than one occasion been favoured with a loan for purposes of comparison. To return them again to the donors was unsatisfactory, and to distribute them in any other way was a breach of good faith.

The products of combustion are so completely deprived of the heat they brought out of the heating chamber K, by passing among the regenerator bricks, that the heat in the chimney-flue is seldom sufficient to singe wood; the economy is therefore due to the fact that little or no heat is thrown away up the chimney, as in the ordinary furnaces, and also to the perfect combustion of the fuel, which is evidenced by the total absence of smoke from the stack; whereas in the common furnaces the combustion is so imperfect that clouds of powdered carbon, in the form of smoke, envelope all manufacturing towns, and gases are allowed to escape with two-thirds of their heat-put ing power undeveloped.

The saving of fuel in these furnaces, as compared to the ordinary kind, ranges between 40 and 60 per cent. in weight, according to the fuel used. In many instances an additional saving can be made in the cost of the fuel

Mr. J. NEWLANDS spoke in favour of the desirability of forming a museum of chemical specimens.

The PRESIDENT reminded the Society of the limited nature of the accommodation at Burlington House, and to the vote the original motion, which was carried by a large majority.

The minutes of the last ordinary meeting were then read, and the donations to the Society's library announced; after which the members proceeded to ballot for the election of Mr. William Marriott, of Huddersfield, and Mr.

Charles Umney, 40, Aldersgate Street, London, both of whom were duly elected as Fellows. The names of the following candidates were read for the first time :-viz., John Percy, M.D., F.R.S., Lecturer on Metallurgy, Royal School of Mines; Ernest T. Chapman, George Street, Portman Square; Charles N. Ellis, Bow Common; and Thomas Ward, Bolton. For the second time were read the names of John Hunter, M.A., Queen's College, Belfast; Theodore Maxwell; William Jacob Barnes, Starling Lodge, Buckhurst Hill, Essex; W. E. Bickerdike, Dalton Square, Lancaster; Richard Fitz' Hugh, Nottingham; Dr. William B. Ritchie, Belfast; and Alfred G. Brown, M.R.C.S, Trinity Square, Southwark.

A paper" On Nitro-Compounds (Part II.), with Remarks on Isomerism," by Edmund J. Mills, D.Sc., was read by the Secretary. The author's experiments were mainly directed to the chemical examination of the alpha and beta varieties of nitrobenzoic acid, and to the remarkable differences observed in the action of hydriodic acid upon them, which are considered as indicating a difference between the nitryl radicals they contain. Reference was made to a former paper in which this view was first advanced, and the author believes he has established the following facts and inferences-viz., that benzoic acid prepared from gum benzoin is nitrated only with difficulty, whereas that obtained from B-nitrobenzoic acid is nitrated with remarkable ease. A mononitro-compound is obtained as the usual product of the first reaction, whilst in the latter case a dinitro-compound is formed. By raising now the energy of the mode of attack (by employing a mixture of concentrated nitric and sulphuric acids), the author has succeeded in procuring the dinitrobenzoic acid at once from the ordinary variety of benzoic acid, and the fusing points and other physical characters are found to be nearly identical with those presented by the product of the action of nitric acid alone upon toluol, and described under different names by Fischer, by Wilbrand and Beilstein, and much earlier, by Abel. Dr. Mills thus recognises two species of benzoic acid, which may, perhaps, bear a fundamental relation to the two potassic benzoates discovered by Gregory. The concluding part of the paper is devoted to a critical examination of the nature of isomerism, and the author controverts the ordinary view which supposes that all bodies are constituted of atoms fixed in space, and that isomeric substances are produced by a variation of the position of some radical or radicals in the same molecule. On the other hand, the author advocates the principle of atomic motion-so largely accepted in physics, so little in chemistry-and believes that the energy of the chemical reaction at the moment of transfer of the nitrylradical may confer upon it specific functions, and may account for the differences observed in the isomers--in fact, that it is altogether a question of force.

Dr. ODLING remarked that the paper before them was one which deserved a careful study, and he regretted, from its having so recently come in possession, that he could not follow the author, on first reading, so closely as he should have wished. He understood that Dr. Mills contradicted the results of Fittig and others, and argued the existence of special functions on the part of the nitryl, denying the necessity of replacing any particular atom of hydrogen in a compound molecule by NO.

Dr. HUGO MULLER said that, so far as he could follow the subject of the interesting paper just now read, it appeared to him that Dr. Mills had somewhat changed his views regarding the nature of the nitro-compounds, and seemed now more inclined to ascribe the difference of deportments of the nitryl (NO2) in various nitro-compounds, when they are submitted to the action of reducing agents, rather to the peculiar nature of the "rest" than to the polymeric nature of the nitryl which he sought to establish in his former paper. With regard to the formation of nitrodracylic acid from toluol, the speaker said that the quantities of nitro- and dinitro-toluol formed

along with it depended in all probability on the mode of conducting the operation. State of concentration and time of action of the acid must influence the result. Toluol when acted upon by dilute nitric acid is gradually, but entirely, converted into benzoic acid, nitrodracylic acid, and a very soluble and readily fusible acid, which may be identical with the one just described by Dr. Mills, as having been formed by the action of nitric acid upon the benzoic acid obtained from amidodracylic acid.

Dr. ODLING then referred again to some passages in Dr. Mills' paper, from which it appeared that he still entertains the views expressed on a former occasion with regard to the nature of the nitro-compounds.

Dr. MULLER then said it required a closer study of the author's paper to enable one to enter upon a discussion of it, but he still thought that the assumption of the nitryl occupying different places in the ordinary nitrobenzoic acid and the nitrodracylic acid, would suffice to account for the differences exhibited by these bodies. Some years ago, when engaged, conjointly with Dr. De la Rue, in the investigation of the products of the action of dilute nitric acid on the homologues of benzol, he had prepared a large quantity of benzoic acid from toluol, which, although subjected to various treatments for the purpose of purification, yet showed a certain peculiar difference from ordinary benzoic acid, and this gave rise to the opinion that the acid in question was identical with Kolbe and Lautemann's salylic acid. Fittig, however, proved afterwards the identity of this acid with benzoic acid. A minute admixture of some other substance was the cause of this difference, and on repeating Fittig's experiments benzoie acid was obtained, which in every respect was identical with the ordinary benzoic acid. As in all probability the acid obtained by the action of dilute nitric acid upon toluol is identical with that obtained from amidodracylic acid, and inasmuch as this latter, according to Dr. Mills's experiments, shows a certain difference from ordinary benzoic acid in its deportment with concentrated nitric acid, the acid obtained from toluol might, after all, turn out to be not identical, but isomeric, with benzoic acid.

Professor G. C. FOSTER said he was well acquainted with the views held by his friend and former colleague, Dr. Mills, and that he conceived the existence of two kinds of nitryl, one of which could be reduced to nitric oxide, and the other to amide by the same mode of treatment. The speaker did not, however, give his assent to Dr. Mills's views.

The PRESIDENT moved a vote of thanks to the author for his interesting communication, and then declared the meeting adjourned until Thursday, December 7, when Dr. J. H. Gladstone would read a paper " On Pyrophosphotriamic Acid."

PHARMACEUTICAL SOCIETY.

Wednesday, November 1.

Mr. HILLS, Vice-President, in the Chair. MR. HANBURY read a paper by Mr. L. W. Stewart, of the Madras Army, "On the Medicinal Uses of the Indian Species of Barberry." It was stated that a strong tincture of the bark in combination with liquor arsenialis had been found useful in cases of intermittent, remittent, and typhus fevers. The author conjectured that a tincture of the kind was one of the ingredients of Warburg's fever tincture.

From a conversation which followed the reading of the paper, we gathered that the composition of Warburg's fever tincture was still a secret, and its value doubtful. It was formerly furnished to Indian troops by the Government, but its use had been discontinued, and now little was sold in India.

Professor REDWOOD read a short communication by Mr. Barber "On Red Oxide of Mercury Ointment.”

The

author recommended the use of yellow in place of white wax. The formula recommended was as follows:-Red oxide of mercury, 1 part; yellow wax, 2 parts; almond oil, 6 parts. An ointment made in this way kept its colour, and did not become rancid. The Professor afterwards mentioned some cases in which colouring matter seemed of some importance. One was that of ceratum saponis, which made with brown vinegar was a much more satisfactory preparation than when made with acetic acid. Mr. HANBURY spoke of the importance of the use of pure white wax in pharmacy, and more particularly in the preparation of cold cream.

The CHAIRMAN mentioned that pure white wax is always sold in square blocks; that in round cakes is always adulterated. He added that the keeping of ointments sweet was a matter of great difficulty; but a most important point was never to fill a pot without having it well cleaned and | scalded out.

Dr. ATTFIELD mentioned a gross case of quack imposture. He had had forwarded to him a white powder imported from France, and sold here as solid cod liver oil. On examination, it proved to be nothing more than sugar of milk, barely flavoured with cod liver oil.

[Can any one tell us what cod liver oil pills are made of? We have seen in a window in Fleet Street a large bottle of brown cod liver oil, having a comparatively small hollow stopper filled with pills; a label attached states that the pills in the small stopper have the medicinal value of the oil in the big bottle.-ED. C. N.]

In the course of a conversation introduced by a reference to the Excise interference with the sale of quinine wine, Professor REDWOOD took the opportunity of stating his view of the law as it relates to the retailing of drugs. It was derived from a leading article in the Pharmaceutical Journal for August, 1843, embodying extracts from a pamphlet published in 1830 on the Stamp Acts passed in the years 1802 and 1812, which if they have never been repealed, have never been enforced, nor held authoritatively to be open to the construction sought to be put upon them. The Professor's opinion is most concisely expressed in the concluding sentence of the article mentioned. "It would appear. that grocers, oilmen, hucksters, and other unqualified persons, cannot legally sell medicines, either simple or compounded, without taking out a license, and cannot sell compounded medicines, such as tinctures, pills, &c., without attaching a stamp to each article."

ACADEMY OF SCIENCES.

November 13, 1865.

We may notice the last paper in the Comptes Rendus first, as being the most important. It is a note, by M. Campisi, announcing the formation of "A Compound of Mercury and Benzyle Hg(Є,H7)2.' The method by which he has prepared it is not yet given. The compound is found to crystallise in white needles, which fuse at a temperature above 200° C. It is slightly soluble in cold alcohol, more so in boiling alcohol, and more soluble still in ether. By means of this compound the author hopes to obtain other metallic compounds with benzyle.

The next paper in importance is a note by M. Baudrimont, "Researches on the Nature of White Phosphorus," in which he establishes that white phosphorus is neither a hydrate nor an allotropic state of ordinary phosphorus, and that it does not result from a sort of devitrification of transparent phosphorus; but that it is, in fact, merely ordinary phosphorus irregularly corroded on the surface by the action of air dissolved in the water, a slow combustion which is accelerated by the action of light, and which ceases as soon as the water holds no more oxygen in solution. We give some of the experiments which appear to decide the matter. Phosphorus covered

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with a white crust lost next to nothing in drying, while a stick of transparent phosphorus exposed in distilled water lost weight as it became covered with the crust. If the crust had been a hydrate, an increase of weight would have been observed. On becoming covered with the crust phosphorus loses none of its properties; its solubility and fusion point remain exactly the same, and it is as readily transformed into red phosphorus. Hence it would appear that nothing like an allotropic difference is observable. Lastly, it is shown that water deprived of air and oxygen has no effect on semi-transparent phosphorus, while other specimens kept in water containing air, and often renewed, become covered with the white crust, the water becoming acid from the formation of phosphorous acid.

M. Oppenheim presented a "Contribution to the History of Allylene." In continuation of his researches, the author has studied the action of oxygenated salts on the compounds of allylene, with iodine, bromine, and hydriodic acid. He prepares iodide of allylene in quantity by exposing allylene in contact with a solution of iodine in iodide of potassium to sunlight, in sealed flasks, for a couple of months. The iodide formed is an oily body, which distils from 196° to 200°. Salts of silver, acetate and oxalate for example, sealed tubes with these salts and with ether or glacial act on the iodide with difficulty; but when heated in acetic acid, the iodide of allylene is almost completely carbonised. An alcoholic solution of acetate of potash acts on the iodide, setting allylene free, while the acetic acid and alcohol form acetate of ethyl. To form acetic acid hydrogen is necessary, and therefore a part of the iodide of allylene should be reduced to C2H22 or C2HI; but the author has not yet been able to prove the presence of such bodies. Bibromide of allylene behaves with regard to the salts of silver like the iodide. The reaction of tetrabromide of allylene with alcoholic acetate of potash is very definite, and is represented by the following equation:

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In this reaction it is seen that the tetrabromide of allylene does not behave as the bromide of a hydrocarbide, but more like the hydrobromate of a bromated hydrocarbide -the hydrobromate of bromated propylene, for example, C2H,Br2HBr.

Thus the bromine of the bromides of allylene seems to be united with the carbon as strongly as the hydrogen; the bromine, so to speak, has entered into the radical, and then the bromides of allylene behave like substitution products, which do not exchange their bromine for the residue HO.

The product of the above reaction, CH,Br3, tribromated propylene, is an unstable, colourless body, boiling at 183 -185°, and is distinguished by this characteristic from the isomeric compound formed by Liebermann by the action of bromine on allylenide of silver (C,H,Ag). This latter body, which may be regarded as bibromide of monobromated allylene, is completely destroyed by boiling.

Tribromated propylene exposed to the light with bromine is slowly transformed into a solid pentabromide, or bibromide of tribromated propylene. It crystallises from ether in beautiful prisms. Allylene is combined with hydriodic acid by introducing a concentrated solution of the acid into flasks filled with allylene. Heat is disengaged, and a heavy oil, bihydriodate of allylene, is formed. Alcoholic potash reduces this body to monohydriodate, which has nearly the same boiling-point as its isomer iodide of allyl, from which, however, it is distinguished by its behaviour towards bromine, and also by its odour.

M. C. W. Blomstrand made another communication on the "mysterious" metal Niobium. The author has

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