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so that a tray of acid sawdust in the purifier remains for months without being saturated. After this complete removal of ammonia, the gas should be submitted to the action of wet lime, or, failing this, on sanitary grounds, to oxide of iron; and lastly to a few trays of dry lime to remove carbonic acid, which, as I shall show you directly, is a very objectionable constituent of gas, on account of its lowering the illuminating power.

The order, then, of purification is:-1st, slow but complete cooling; 2nd, washing with ammoniacal liquor; 3rd, the removal of ammonia by water or acid; 4th, the abstraction of sulphuretted hydrogen by lime or oxide of iron; and 5th, carbonic acid. I have been particular in recapitulating all this because of its great importance in the manufacture of good gas.

sulphuretted hydrogen, the ammonia, and the other impurities which still remain in it. In continuation of the system already adverted to, it is well to submit the gas to the action of a copious stream of ammoniacal liquor after it leaves the purifiers. As far back as the year 1846, Mr. Lowe directed attention to this, and he patented a process for effecting it. Very recently Mr. Hawksley has, from independent observations, and from a chemical consideration of the subject, recommended a like process.* He advises that the gas should be drenched with ammoniacal liquor to the extent of a sixteenth of the volume of the gas. The effect of this is to strengthen the liquor and to remove from the gas ammonia, sulphuretted hydrogen, carbonic acid, and the objectionable compounds of sulphur with carbon, and the hydrocarbons. In practice it is found that the gas thus treated never contains more than twelve We will now pass on to the proper subject of the lecture grains of sulphur in any form in 100 cubic feet-the-namely, the examination of the chief constituents of average being about nine and a-half grains; and, to use purified coal gas. These may be classed under three the words of your president, "it thus appears that all heads :considerable gas companies may, by a very simple, and in The combustible non-illuminating constituents. other respects very useful process, remove a large propor- 2. The illuminating hydrocarbons. tion of the objectionable sulphur compounds which usually 3. The impurities. continue to exist in coal gas after it has been passed through lime or other metallic oxide."

The residual impurities—namely, the ammonia, sulphuretted hydrogen, and carbonic acid are next to be removed in proper order. Washing the gas with water, or with weak ammoniacal liquor, and finally with water, will at once abstract a considerable amount of all these impurities; and although there is a prejudice with some engineers that this kind of purification is objectionable on account of its lowering the illuminating power of gas, yet, as we shall see hereafter, the prejudice is not founded on fact-excepting that the process undoubtedly removes such compounds as tar and naphthaline, which, though of high illuminating power, are nevertheless better out of the gas than in it, seeing how much mischief they do by subsequent deposition in the mains and service pipes. You will have an opportunity of seeing at the Saltley station of the Birmingham and Staffordshire Gas Company, in this town, the good effect of thoroughly washing the gas with water or weak ammoniacal liquor before it passes to the purifiers. Mr. Young, the experienced engineer of the Company, has for some time past adopted this practice. The gas, on leaving the condensers, traverses successively three washers, or as they may be more properly called, douche scrubbers; each of them is 25 feet high, 8 feet long, and 4 feet wide; and the liquor or water is delivered into them at the rate of 1815 gallons an hour, the gas passing at the rate of about 66,000 cubic feet an hour. The water or liquor flows through a pipe or jet with a very small orifice, and dashing upon a disc immediately below it, is splashed out into a fine shower which meets the ascending gas. The rate of flow, therefore is about 274 gallons for every 1000 cubic feet of gas. In this manner the gas is thoroughly cleansed before it goes to the purifiers, and the contrivance is such that no pressure is put upon the gas, for it passes through the washers without friction. The quantity of ammoniacal liquor which is thus obtained amounts to 44 gallons per ton of Staveley coal, the strength of the liquor being 4 of Twaddle, or about 8 ounces of sulphuric acid. Before this process was adopted, the quantity of liquor of the same strength was only 25 gallons per ton; and the profit arising from the sale of the liquor is more than 2000l. per annum in excess of the former returns. I find from an examination of the gas, that its illuminating power is from 15 to 16 sperm candles of standard quality, and that there is no loss of power by deposition in the mains-the gas, indeed is absolutely free from ammonia, naphthaline, and carbonic acid, and the amount of sulphur in any form does not exceed 16 grains per 100 cubic feet. When the gas has been thus washed, it contains but little ammonia, * Journal of Gas Lighting, vol. xiii., p. 542.

I.

1. The Combustible Non-Illuminating Constituents of Coal Gas. These form a very large proportion of its bulk-as from 30 to nearly 60 per cent. They are hydrogen and carbonic oxide; and their sole function seems to be the purveying or carrying the illuminating hydrocarbons.

(a) HYDROGEN (H) exists in coal gas to the extent of from 12 to nearly 50 per cent. It is in greatest abundance in poor gas of low illuminating power, and it no doubt comes in great part from the decomposition of the richer hydrocarbons by the high temperature of the retorts. It is also produced by the moisture of the coal giving up its oxygen to the red-hot carbon, and setting free its hydrogen. The gas is singularly inert-it has no colour, no taste, no odour, and no action on the human body. It is the lightest body known, its specific gravity being o'0692, atmospheric air being 1; and 100 cubic inches of it weigh only 2'15 grains, the same quantity of air weighing 31 grains. It burns without any light; and, as you perceive when I hold a cold glass over the flame, the product of its combustion is water. One cubic foot of hydrogen requires half a cubic foot of oxygen, or 2 cubic feet of atmospheric air, for combustion. The temperature of the flame is very highabout 5898° Fahr., and a cubic foot of the gas, in burning, will raise 5220 ounces of water, or 16,250 cubic feet of air, 1° Fahr. Lastly, it is but slightly absorbed by water -100 volumes of water taking up about 1'93 of hydrogen gas; and it is not condensable by cold or pressure.

(b) CARBONIC OXIDE (CO) is a compound of one proportion of carbon and one of oxygen. By weight, therefore, it consists of 6 parts of carbon and 8 of oxygen; and by volume, of half a volume of carbon vapour and half a volume of oxygen, united without any condensation. It is not a large constituent of coal gas, the proportions ranging from about 5 to 16 per cent.; but it forms a considerable part-about 34 per cent.-of the gas made by the decomposition of steam by red-hot carbon. This, indeed, is the chief source of it in common coal gas. Like hydrogen, it is colourless and odourless; but, unlike it, it is a deadly poison. I have ascertained that 2 per cent. of it in air will kill birds almost instantly; and, according to Leblanc and Dumas, an atmosphere containing one per cent. of it will kill a small dog in a minute and a-half. It is a little lighter than atmospheric air, in the proportion of 0.967 to ; and 100 cubic inches of it weigh nearly 30 grains. It burns with a pale bluish and somewhat opaque flame; and, as you here see, it forms nothing but carbonic acid. The flame cannot be got from the small jet over the governor. I am obliged to burn the gas from a very large jet over the pneumatic trough, and therefore I am not able to show you the size of its flame in comparison with coal gas. In the act of burning, 1 cubic foot of carbonic oxide consumes half a cubic foot of oxygen, or 24 cubic feet of

air; and the heat of the flame is very nearly as great as that of hydrogen, it being 5508° Fahr. A cubic foot of it will raise the temperature of 5400 ounces of water, or 16,500 cubic feet of air, 1° Fahr. It is but slightly absorbed by water-100 volumes absorbing 2'43 volumes-but it is very freely absorbed by a strong solution of sub-chloride of copper; and this is the agent used for its detection in coal gas.

2. The Illuminating Constituents (Hydrocarbons) of Coal Gas. These are all compounds of carbon and hydrogen; hence their name, hydrocarbons. And as, in the same volume of the gas, there are very different proportions of carbon, the illuminating power of these several constituents varies considerably. In all cases the light which they evolve in the act of burning is due to their decomposition by the heat of the flame, and to the suspension of the liberated carbon for a definite time in an ignited state.

The following are the principal members of this group, Marsh Gas, C,H,; Olefiant Gas, or Ethylene, C1H1; Propylene, CH; Butylene, C.H.; Acetylene, CH; Benzol, CH; Naphthaline, CH. and perhaps some others.

beginning with the least illuminating :—

(a) MARSH GAS is also called Pit Gas, Fire-damp. Light Carburetted Hydrogen, and Hydride of Methyl (C,H). A volume of the gas contains half a volume of carbon vapour, and two volumes of hydrogen. It is a large constituent of the. gas evolved from sewage, and the mud of a stagnant pool. It also forms from 79 to 91 per cent. of the fire-damp of coal mines, and it constitutes from 30 to 60 per cent. of coal gas. It is colourless, odourless, tasteless, and without action on the animal body, for miners breathe it with impunity. It is a little more than half the weight of atmospheric air-its specific gravity being o'5531; and, therefore, 100 cubic inches of the gas weigh 17.15 grains. It burns, as you perceive, with a pale yellow flame, which is bluish for a considerable distance up, the height of the jet being somewhat less than that of coal gas; and so also is its illuminating power. A cubic foot of gas consumes 2 cubic feet of oxygen, or 10 cubic feet of air; and the products of the combustion are a cubic foot of carbonic acid, and aqueous vapour. The heat of the flame is about 5890° Fahr., and a cubic foot will raise 16,920 ounces of water, or 52,000 cubic feet of air, 1° Fahr. The gas is but slightly absorbed by water-100 volumes taking up 3'91 of the gas. It is not absorbed by chlorine, except after some time, and in the light; nor by bromine or fuming sulphuric acid; and it is not easily decomposed by heat; nor is it condensed by cold. There is no immediate test for the gas.

Besides marsh gas, there are probably other members of the series present in coal gas, as Ethyl-hydride (CH). Propyl-hydride (CH), Butyl-hydride (CH10), and Amyl hydride (C10H12), all of which are found in the petroleums of commerce.

(b) OLEFIANT GAS, ETHYLENE, or ELAYL (CH), is a gas which contains twice as much carbon in a given volume as the last-a volume of it contains its own bulk of carbon vapour and two volumes of hydrogen. It exists in fire-damp to the extent of from 2 to 16 per cent., and in coal gas too from 8 to 27 per cent., cannel gas containing it in the largest proportion. It is colourless, and, when pure, is a little ethereal or sweetish in its odour, and it is anæsthetic or stupifying in its action on the body when it is inhaled. It is very nearly as heavy as atmospheric air-its gravity being o'967; and, therefore, 100 cubic inches of it weigh nearly 30 grains. It burns with a long, bright yellow flame, the illuminating power of which is fully twice as great as the last. A cubic foot of the gas requires 3 cubic feet of oxygen, or 15 cubic feet of air for its combustion, and it produces 2 cubic feet of carbonic acid, and much aqueous vapour -evolving about one-third more heat than the last.

When mixed with twice its volume of chlorine gas and fired, its hydrogen is consumed, and its carbon is deposited in the form of soot. It is also slowly absorbed by chlorine, in the dark as well as in the light, forming a heavy oily liquid of an ethereal odour, called Dutch liquid (C,H,Cl). In like manner it is absorbed by bromine, and by fuming sulphuric acid. The gas is slightly soluble in water, to the extent of about one-eighth of its volume, and it is freely soluble in alcohol, ether, volatile oil, and fixed oil. Turpentine, for example, will take up twice and a-half times its volume of the gas, and olive oil will absorb its own volume of it. It is easily decomposed by heat-a red heat converting it into carbon and marsh gas, together with a small quantity of tarry matter; and the gas is condensable by great cold and by pressure. The test for the gas is bromine or fuming sulphuric acid, which freely absorb it.

(CI), is a compound of carbon and hydrogen in the (c) PROPYLENE, or, as it sometimes termed, Tritylene

same percentage proportions by weight as the last; but a volume of it contains 1 volume of carbon vapour and 3 volumes of hydrogen. Its proportion in coal gas has not been accurately determined. It is colourless, and has a stupifying action on the body. It is just half as heavy again as atmospheric air-its specific gravity being 1'455; and, therefore, 100 cubic inches of it weigh about 45 grains. It burns with a bright yellow and somewhat sooty flame, which is fully three times as long as the comparison jet of coal gas burning from the same sized orifice, and under the same pressure; and the light evolved from it is about three times as great as that from common coal gas. A cubic foot of it requires 4 cubic feet of oxygen, or 224 cubic feet of air, to burn it; and it produces 3 cubic feet of carbonic acid, and much aqueous vapour. The heat evolved by it is also very great. It is but slightly absorbed by water, but it is freely absorbed by chlorine, bromine, and iodine, forming compounds which correspond to Dutch liquid. It is also absorbed by fuming sulphuric acid, and even by strong oil of vitriol. The volatile and fixed oils dissolve it, and so also does a solution of proto-chloride of copper. As in the last case, it is readily decomposed by a red heat, forming marsh gas, and depositing carbon; and it is also condensed by cold and pressure.

(d) BUTYLENE, TETRYLENE, DITETRYL, or Oil Gas (С.H ̧), is a still further condensation of carbon and hydrogen in the same per-centage weights as in olefiant gas. A volume of butylene contains two volumes of carbon vapour and four of hydrogen. It is a large constituent of oil gas, and it exists in cannel gas to the extent of about from 3 to 4

per cent.

Common gas contains it in very small proportions. The gas is colourless, and it has a peculiar odour. Its action on the body is not known, but no doubt it is anæsthetic, like the other hydrocarbons of this Leries, It is nearly twice as heavy as atmospheric air, its gravity being 1935; and, therefore, 100 cubic inches weigh just 60 grains. It burns, as you perceive, with a long sooty flame, the jet being nearly four times as long as the comparison jet of coal gas; and the illuminating power of it is about four times as great as the jet of common gas, A cubic foot of the gas requires 6 cubic feet of oxygen, or za cubic feet of air, to burn it; and the products of its combustion are 4 cubic feet of carbonic acid and much aqueous vapour. Like the other hydrocarbons, it is but slightly soluble in water, but it is freely dissolved by alcohol and by the fixed and volatile oils; olive oil, for example, absorbs about six times its volume of the gas. It is also absorbed by chlorine and bromine, forming compounds analogous to Dutch liquid; and it is likewise freely absorbed by sulphuric acid, a volume of the acid taking up 100 volumes of the gas. If it is passed through a red-hot tube, it is decomposed and resolved into marsh gas, hydrogen, and carbon. It is also easily condensed by cold and pressure, forming a thin, transparent, and colourless oil,

NEWS

of which I show you a specimen. In the days of oil gas when the Compressed Gas Company was in existence, this ethereal oil was produced in rather large quantity; 1000 cubic feet of the gas submitted to a pressure of 30 atmospheres produced about a gallon of oil, composed almost entirely of butylene, with benzole and an oil of doubtful composition. It was from this mixture that Faraday obtained butylene.

(e) ACETYLENE, or Klumene (CH). A volume of this gas contains its own volume of carbon vapour and one volume of hydrogen. The gas exists in but very small proportions in coal gas; and it is remarkable as being a hydrocarbon which can be obtained by the direct union of carbon with hydrogen, by igniting carbon, by the aid of electricity, in an atmosphere of hydrogen. It can also be obtained by exposing a mixture of carbonic oxide and marsh gas to the action of a high temperature,-a circumstance which may hereafter be of practical utility in the manufacture of gas. It is likewise a product of the decomposition of hydrocarbons by heat. The gas is colourless, with a peculiar odour, and it is probably anæsthetic. It is a little lighter than air, the specific gravity of it being 0898; 100 cubic inches therefore weigh just 28 grains. It burns with a brilliant light, as you here perceive, and with a sooty flame, considerably longer than the flame of coal gas; and when I mix it with a large volume of hydrogen gas, it still burns with a bright flame. A cubic foot of the gas requires 24 feet of oxygen, or 12 feet of air, to burn it; and it produces two volumes of carbonic acid, and aqueous vapour. The gas is freely absorbed by water to the extent of its own bulk, and it is again expelled unchanged when the water is boiled. It also combines, with great energy, with chlorine, bromine, and sulphuric acid. The best absorbent for it is a solution of ammonio-subchloride of copper. The solution is made by mixing a dilute solution of chloride of copper with an equal bulk of pure muriatic acid, and shaking the mixture in a bottle with copper filings, or boiling it with copper turnings until it is colourless. The solution is then put into a bottle or flask, with three tubes adapted to it: one for delivering the coal gas into the solution, a second for the exit of the gas, and the third for pouring in a strong solution of ammonia. When the gas has displaced all the air from the bottle, ammonia is poured into the solution until a deep blue liquid is obtained; and this, as you here see, absorbs the acetylene of the gas, and produces a chocolate or reddish brown precipitate of acetylide of copper (C,H,Cu2), which is a compound in which two proportions of copper have replaced one of hydrogen. This acetylide of copper is to be collected on a filter, washed with water, and dried. If it is heated in a flask, as I am now doing, with dilute muriatic acid, it is decomposed, and the acetylene escapes with effervescence. You will notice, too, with what a bright yellow flame the gas burns.

12

(f) BENZOL, or, as it is sometimes termed, Benzine, Phene, or Bicarburetted Hydrogen (C12H6). One volume of this vapour contains three volumes of carbon vapour and three of hydrogen. It exists in coal gas in very variable proportions. At times it is but barely discoverable, and at other times it is present in large quantity. It is often present in London gas to a considerable extent, and I attribute it to the practice which is occasionally followed of pouring light naphtha into the mains for the purpose of removing naphthaline. I here show you a specimen of nitro-benzole obtained from only 15 cubic feet of gas. The vapour of benzole is colourless, and it has a peculiar odour, which is rather agreeable when the benzole is pure. It is powerfully anaesthetic, and will cause fatal insensibility if it be inhaled too copiously. The vapour is about 2 times as heavy as atmospheric air, its specific gravity being 2.695; 100 cubic inches of it will, therefore, weigh 84 specific grains. The vapour burns with a very bright light-so much so that I have no difficulty in giving a strong illuminating power to hydrogen by merely passing

the gas through a tube containing a little tow moistened with benzole. This is a good example of the naphthalisation of gas; and I have here another instance of it where coal gas is passing over the benzole contained in a proper naphthaliser. You perceive the extraordinary richness of the light. Experiments have been made for the purpose of determining the value of the light for the benzole or naphtha consumed; and the results are, that every grain of the vapour taken up by a foot of common twelve-candle gas increases its light about 10 per cent. The various naphthas of commerce are more or less charged with benzole and its homologues, and they raise the illuminating power of gas from 4 to 8 per cent. for each grain of the vapour absorbed by the gas. In the act of burning, a cubic foot of benzole vapour consumes 7 cubic feet of oxygen, or 37 cubic feet of air; and it produces 6 cubic feet of carbonic acid, and much aqueous vapour. The heat of the flame also is considerable. Benzole is but slightly absorbed by water, but is freely taken up by alcohol, ether, and the volatile and fixed oils. It is also, like the other rich hydrocarbons, absorbed by vulcanised tubing. The vapour is slowly condensed by chlorine and bromine in the sunlight, and compounds are formed containing six proportions of the halogens (C12HCl, and C,H&Bre), which present a certain analogy to Dutch liquid. Sulphuric acid also absorbs the vapour, and forms conjugate acids; but the most interesting product of ben. zole is its substitution compound with peroxide of nitrogen, which is produced when it is brought into contact with strong nitric acid. This, indeed, is the test for benzole; so that if coal gas is passed through fuming nitric acid, as you here see, the benzole vapour is absorbed, and an oily liquid is produced, which has the odour of bitter almonds. This is easily purified by washing it with water, and finally with a weak alkaline solution. It is then called Nitrobenzole, or Essence of Mirbane. It is produced from benzole by the substitution of one proportion of peroxide of nitrogen for one of hydrogen (C12HNO1); and I may remind you that, although it is used very largely in perfumery, it is a dangerous poison; I know instances where a few drops of it have produced fatal coma. Benzole vapour is decomposed by a red heat, forming a gaseous hydrocarbon, and depositing much carbon. It is also easily condensed by cold, when it forms an ethereal liquid, which freezes into a crystalline solid at 32°, and which boils at 177° Fahr. This liquid is lighter than water, and is remarkable for its solvent power for caoutchouc, guttapercha, and all kinds of resins and fats.

(g) The other members of the benzole series, as Toluol (CH), Xylol (C16H10), Cumol (C18H12) and, Cymol (CH), are no doubt also present in coal gas, for they are found in the naphtha distilled from coal tar; but as they are less volatile than benzole, they are present in smaller quantity.

(h) NAPHTHALIN (CH) is the last of the hydro, carbons to which I shall refer. It is only present in gas which has been made at high temperature, and it is invariably a secondary product of the decomposition of the richer hydrocarbons (tar, &c.) by the walls of the redhot retort. In London, where it is the practice to work at very high temperatures, the coal gas is always charged with naphthalin, and its presence in the mains is a serious inconvenience. The vapour of naphthalin is very rich in carbon-a cubic foot of it contains five times. its bulk of carbon vapour, and four times its bulk of hydrogen. The specific gravity of the vapour is 4'422, and therefore 100 cubic inches of it weigh rather more than 137 grains. It burns with a bright sooty flame, and if I heat a little of the hydrocarbon in a flask, and pass hydrogen gas through it, you will see how richly it naphthalises the gas. In the act of burning, a cubic foot of the vapour consumes twelve times its volume of oxygen, sixty times its bulk of air, and it forms 10 cubic feet of carbonic acid and aqueous vapour. Naphthalin is not absorbed by water,

but it is by the volatile and fixed oils, and by naphtha and coal-tar; hence the advantage of keeping the raw gas until it is thoroughly cooled in contact with tar and ammoniacal liquor in a long hydraulic main. Hence, also, the fact that the richer qualities of gas, containing much hydrocarbon, do not deposit naphthalin; and hence, also, the use of naphtha as a remedy for naphthalin in the mains and service-pipes. The vapour of naphthalin is absorbed by chlorine and also by bromine, the products being liquids which have considerable analogy to Dutch liquid. It is also absorbed by sulphuric acid. Naphthalin is not easily decomposed by heat; it is quickly deposited by cold, forming brilliant white scales, which have a tendency to collect in the bends of pipes, and wherever there is an impediment to the easy flow of the gas. These scales are slowly volatile at ordinary temperatures, they melt at a heat of 174° Fahr., and they boil at 428°. (To be continued.)

ACADEMY OF SCIENCES.

June 19, 1865.

A NOTE "On the Extraction of Sugar," by M. Alvaro Reynoso, of Havannah, was read. The author uses acid phosphate of alumina, which he neutralises carefully with lime for clarifying the cane juice. Alumina and phosphate of lime are precipitated, and carry down effectively the colouring and nitrogenised bodies. The author has also an ingenious way of getting rid of the bulk of the water in the juice. By some process described in his memoir, but not quoted in the Comptes Rendus, he submits the juice to a very low temperature, and so gets a magma composed of thick syrup and little lumps of ice. He separates the syrup from these by means of a centrifugal machine, and then evaporates quickly in vacuo. M. Canizzaro continued his memoir "On the Amines of Benzoic Alcohol." He described the method by which he obtained dibenzylic toluidine :

N

{

(C,H,)a (C,H-)b (C-H2b

in which formula (C-H-)a stands for cresyle, and (CH)b for benzyle. The behaviour of the platinum salt of the weak alkaloid proves it to be isomeric with tertiary benzylamine. The author has made many attempts to prepare primary benzylamine free from the secondary and tertiary amines, but without success. He finds that the greater part of the chloride of benzyle is always converted into the secondary and tertiary alkaloids-a fact which connects the benzoic with the methylic series. Canizzaro intends to continue the comparative study of primary benzylamine and toluidine. Considering phenols as bodies intermediary between alcohols and acids, he regards aniline and similar alkaloids as coming between amines (those properly so called) and amides; and he hopes to show that while toluidine, in acting upon other alkaloids by incomplete substitution, disengages ammonia and replaces hydrogen by the radical cresyle (C,H,)a, benzylamine, under the same conditions, will do no such thing.

June 26.

Two communications on the woorari, or curara poison, were read. We notice first that by M. Preyer, "On the Active Principle of Curara." To prepare the alkaloid, the author treats the crude poison, scraped off arrows or obtained from the Indians in little clay pots, with boiling alcohol, and distils the alcohol from the solution. The residue is treated with water and filtered to separate the resin, and the filtrate is precipitated by bichloride of mercury. This precipitate contains all the curarine. It is washed, suspended in water, and decomposed by sulphuretted hydrogen; and thus hydrochlorate of curarine is obtained in solution. The purification may be effected as

usual in such cases. Another way of procuring the alkaloid is to treat the aqueous solution obtained as above first with a few drops of nitric acid, and then with phosphomolybdic acid. The bulky precipitate is decomposed by hydrate of baryta, and the mixture is dried and the mass exhausted with absolute alcohol, which takes up scarcely anything but curarine. An analysis of the chloroplatinate leads to the formula €10H15N for this alkaloid, which is seen to be destitute of oxygen. There is but one other instance of a natural alkaloid not containing oxygen. Curarine may be obtained in crystals by leaving a chloroform solution to spontaneous evaporation.

The soluble salts are all crystallisable; of the insoluble the chloroplatinate alone has a crystalline appearance. The alkaloid and the soluble salts crystallise in four-sided prisms. Curarine has a persistent bitter taste, is soluble in water and alcohol in all proportions, is but slightly soluble in chloroform and amylic alcohol, and is altogether insoluble in ether, benzole, turpentine, and sulphide of carbon. Pure concentrated sulphuric acid gives to curarine a magnificent and lasting blue colour, which reaction will serve to distinguish it from strychnine. colour as with strychnia, but with curarine the colour Bichromate of potash with sulphuric acid gives the same is much more lasting. Strong nitric acid produces a in animals. Alcohol extracts it, and it may be identified purple colouration. The poison may be easily discovered by the above reactions. poison is obtained from many plants; he has extracted it himself from the dried fruit of the Paullinia cururu. logical Effects of Curarine," by M. Claude Bernard, who tells us that the effects of the alkaloid resemble exactly those produced by the substance from which it is obtained, but are, of course, much more intense. Like the woorari itself, it is absorbed with great difficulty by the intestinal canal, but operates with frightful energy when introduced into a wound. M. Bernard promises another communication relating to his experiments on the effects of curarine on the motor nerves.

The author states that the

The other communication was a note "On the Physio

M. H. St. Clair Deville presented a note with the promising title, "On the Industrial Preparation of Alumina and its Compounds, and on their Industrial Applications," but in the note he only tells us that alumina and its compounds are made in large quantities at Newcastle, and at Salindres, from Bauxite. There appears now to be no difficulty in making sulphite of alumina, which would seem to be a good defecator.

A note "On the Employment of Biphosphate of Alumina Desvignes, who claims the first use of this substance, and in the Manufacture of Sugar" was read by M. Kessler moreover the discovery that biphosphate of magnesia will answer just as well as a defecator of sugar juice. Acids, and on their Association in the Mineral Kingdom," by A note "On the Constitution of Hyponiobic and Tantalic M. Marignac, was read. Of this, and another "On a New Process for the Manufacture of Steel," by M. Berard, we shall give abstracts next week.

NOTICES OF BOOKS.

Journal für Praktische Chemie. Nos. 6 and 7. 1865. NUMBER 6 of this Journal contains no paper of interest NEWS. which has not already been noticed in the CHEMICAL In No. 7 we find a paper by C. Gilbert Wheeler "On the Mineral Ingredients in Bavarian Hops," which gives analyses of the ashes of hops from various districts. things, but we have no space for them in our pages. The These analyses deserve a place in a collection of such principal fact learnt from them is the large proportion of potash and phosphates which hops contain, and which points to the composition of a proper manure.

measuring quantities therefrom."-Petition recorded Feb. 14, 1865.

441. W. Kerrage, Gardner's Road, Victoria Park, "An improvement in the manufacture of artificial stone for building purposes."—Feb. 16, 1865.

477. W. E. Gedge, Wellington Street, Strand, "A chemical combustible substance, and apparatus to which it is applicable." A communication from F. Stoker, Faubourg St. Martin, Paris.—Feb. 20, 1865.

The next paper is by Dr. T. Humpert "On the Action of Concentrated Sulphuric Acid on Arseniuretted and Antimoniuretted Hydrogen, with Experiments on the Freparation of Pure Antimoniuretted Hydrogen.” The arsenical gas passed into strong sulphuric acid gives a brown precipitate of a compound of hydrogen, sulphur, and arsenicum, which does not appear to have a constant composition, the proportion of hydrogen and sulphur increasing with the duration of the experiment. A similar compound is obtained when antimoniuretted hydrogen 500. J. Nicholas, Aspull, near Wigan, Lancashire, is passed through sulphuric acid. Sulphuretted hydrogen" Improvements in the process and apparatus for producing is evolved in both instances. To obtain the antimoniuretted oil and coke from coal and slack."-Feb. 22, 1865. hydrogen as free as possible from uncombined hydrogen 511. S. Saville, Bradford, Manchester, "Improvements the author gives the following process. He takes sodium in separating wool from refuse, mixed fabrics, and amalgam, and places it in a flask with a tolerably con- materials." centrated solution of terchloride of antimony. The mixture froths, and antimoniuretted hydrogen escapes, but it is easily decomposed, even at the ordinary temperature. The sides of the flask quickly become coated with a thick layer of metallic antimony. This never happens when the antimonial gas is diluted with a large proportion of hydrogen. When the gas obtained as above is ignited it burns with a pale yellow flame, with the separation of thick fumes of antimonious acid.

Most of the other papers have been noticed, but we find a paper by Von Hauer" On the Easily Fusible Cadmium Alloys," containing some particulars which we shall give in a table. There is also a process by Boettger for “Etching on Zinc, and Gilding the Etched Places," which we give in a miscellaneous paragraph; together with other short notices of a new synthesis of formic acid, a new process for the separation of potassium, rubidium, and cæsium, and a new process for the extraction of indium from Freiberg Blende.

NOTICES OF PATENTS.

512. W. E. Newton, Chancery Lane, "An improved mode of preparing fertilising compounds or artificial manures." A communication from G. A. Liebig, Baltimore, Maryland, U. S. A.—Feb. 23, 1865.

CORRESPONDENCE.

Continental Science.

PARIS, July 2.

ANY addition to the comfort of railway travelling is worthy of notice, and therefore I may mention a plan invented by M. Seris for laying the dust raised by a train. This plan, by the special recommendation of the Emperor, was tried last week on the Bordeaux line, and is said to have satisfied the engineers who witnessed the trial, but I have at present no account of M. Seris' apparatus to give.

I see also a notice of a plan of preventing boiler incrustations which I am inclined to think is not new in England, but I quote it, since it may be new to some. It consists in lining the boiler with a metallic network at

GRANTS OF PROVISIONAL PROTECTION FOR some distance from the sides. The lime salts will of

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1506. H. Allman, Ampthill Square, Middlesex, "Certain improvements in the manufacture of iron and steel, and in apparatus connected therewith."-Petition recorded June 1, 1865.

1573. W. E. Gedge, Wellington Street, Strand, "An improved process for penetrating or impregnating woods with various substances."-A communication from J. L. Hossard, Faubourg St. Martin, Paris.-June 9, 1865. 1582. R. A. Brooman, Fleet Street, "Improvements in kilne for firing porcelain and other ware."-A communication from F. Durand, Paris, June 10, 1865.

1586. J. E. Poynter, Glasgow, N.B., "Improvements in purifying paraffine."

1591. J. Thomas, Battersea, Surrey, "A new material to be used in the purification of heating and lighting gases."-June 12, 1865.

1595.-G. Haseltine, Southampton Buildings, Chancery Lane, Improvements in fuses for shells for ordnance." A communication from F. Schentel, Boston, Mass. U.S.A. 1600. C. J. Collins, Upper Thames-street, London, "A new or improved artificial fuel."

1602. T. Routledge, Ford, near Sunderland, and W. H. Richardson, Springwell, Jarrow-on-Tyne, "Improvements in the manufacture of paper and paper stock, and in the utilisation of certain waste products resulting therefrom."

1605. F. A. Laurent and J. Casthelaz, Rue Sainte Croix de la Bretonneric, Paris, "Improvements in the manufacture of phthalic acid and chloroxynaphthalic acid, and in dyeing and printing."-June 15, 1865.

NOTICES TO PROCEED.

414. W. C. Hine, Swineshead, Lincolnshire, "Improvements in stoppering bottles or other similar vessels, and

course be deposited upon this network, which can be easily removed, and from which the crust can be easily detached.

Dr. Carlier's fire extinguisher I think I have mentioned before, but may return to it again, since its efficacy was satisfactorily shown at the Abbe Moigno's last soirée. The small instrument is really nothing more than a bottle of what is in England called soda-water-that is, water saturated under pressure with carbonic acid. A stopcock lets out, and a pipe directs, the jet of gas and water to the flames, which, of course, quickly succumb. Larger instruments may be made to generate the gas within themselves by special arrangements. I do not see that this apparatus offers any advantage over Phillips's extinguisher.

I mentioned, about a year ago, the laboratory started by MM. Fremy and Chevreul, in which poor and ardent students might work, and have the advice of the two worthy Professors named, gratis. I am happy to say now that M. Duruy, the Minister of Instruction, has made a grant of 10,000 franes, and that M. Ménier has offered to supply the chemicals for nothing, and thus the cost of the establishment has been provided for, although the Professors still superintend it without fee. The generosity of M. Ménier does not end with the supply of the chemicals; a few students who show special aptitude for research receive pecuniary assistance from a fund which he has placed at the disposal of the Professors.

I never remember to have read before an account of the way in which butter is made in Normandy; so, thinking it may be new to others, I translate it from Cosmos. The cream is tied up in a canvas bag, and then buried in a hole in the ground for twenty-five hours. At the end of this time it forms a hard mass, which is broken up with a wooden pestle, whereupon the buttermilk runs away. A small quantity of water is thrown on the butter to rinse

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