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land. We shall describe its properties hereafter ; meantime, we cannot help remarking, that it affords the strongest support to Sir H. Davy's reasoning in relation to chlorine. The prevailing opinion, too, among chemists at present, is, that the fluoric principle, or fluorine, is likewise a simple supporter of combus. tion, and capable of combining, like oxygen, with salifiable bases ; so that instead of one acidifying and incombustible sub, stance, a doctrine which constitutes the very foundation of the Lavoiserian system, we have three or four such substances.

It remains that we give a short view of the combinations formed by chlorine and iodine with the metals and other bodies, and also of the new nomenclature which the progress of the science has rendered necessary. It is expedient, however, to mention, in the mean time, that when a metal combines with two doses of chlorine, these combinations are denoted by changing the termination of the Latin word, by which the metal is known, into ane, and anea. Thus the first compound of iron and chlorine is called ferrune, and the second ferranea *.

1. Copper admits of two proportions of chlorine. Cuprane, the first of these, may be obtained by heating together two parts of oxymuriatic of mercury, and one part of copper filings. It is insoluble in water, effervesces in nitric acid, dissolves in muri. atic acid, from which it is precipitated by water, in the state of white powder. . .

Cupranea is formed by heating cuprane in chlorine gas. It is a yellow powder, absorbs water from the air, is decomposed by a strong heat, and converted into cuprane, even when heated in chlorine gas.

2. Tin, like copper, forms two compounds with chlorine, stannane and stunnanea. The first is of a grey colour, and of a resinous lustre and fracture. The second, long known as the liquor of Lihavius, requires no description. : 3. Iron likewise combines in two proportions, constituting, as mentioned above, ferrane and ferranea, The former is of a greyish colour and metallic splendour, dissolving easily in water; the latter is a volatile substance, and dissolves in water, forming the red muriate of iron. . 4. Manganese admits only one proportion of chlorine, and this combination is usually effected by evaporating to dryness the white muriate of thąt metal, and heating the residue to redness, in a glass tube with a very small orifice. It is a beautiful sub, stance, and denominated, in the new nomenclature, mangan, nesane.

* See Phil. Transactions, 1812.

5. The compound of chlorine and lead, plunbane is obtained by fusing the muriate of lead in a glass tube. Its properties are familiar to every one. "

6. Chlorine and zinc combine in one proportion, forming zine, cane. This is a very deliquescent substance, and is incapable of standing the operation of so strong a heat as is necessary to sublime it. It melts before it is red hot, and on cooling be. comes viscid.

7. The compound of chlorine and arsenic (arsenicane) was formerly called the fuming liquor of arsenic. It is obtained by burning arsenic in chlorine gas. It dissolves sulphur and phosa phorus while hot, but deposites them as it cools.

8. Antimoniane is the uew term for the substance com pounded of antimony and chlorine. It is the “butter of antimony,” of the shops, and requires no description.

9. Bismuth and chlorine unite in one proportion, and form bismuthane. It is got by distilling two parts of the oxymuriate of mercury and one part of bismuth. It is of a greyish white colour, opake, uncrystallized, and of a granular texture *, ..

Chlorine, however, is not confined in its combinations to the metals. It enters into union with oxygen in two different pro. portions, producing what are called by Gay-Lussac, chlorous, and chloric acids. The former of these is denominated by Davy, enchlorine. This gas is distinguished by the facility with which it explodes, not unfrequently on the mere transference from one vessel to another, and always on the application of a very gentle heat : hence the danger of operating on it in large quantities. By explosion in a close vessel, it is resolved into chlorine and oxygen. It is partially decomposed by water, and oxygen is set. free: mercury produces a very slight decomposition. · Chlorine forms with azote a new and very striking compound, which will not fail to be celebrated as having cost an eye to M. Dulong, the discoverer, and as having nearly entailed on Sir H. Davy a similar sacrifice. From the memoirs of these chemists we learn, that azote and chlorine have no perceptible action on each other' when in the gaseous form, but when the latter is passed through a solution of the nitrate of aminonia, it is rapidly absorbed, and a film collects on the surface, which is soon resolved into distinct drops of a yellowish oil, that sinks to the bottom of the liquid. This is the detonating substance in ques. tion. Its smell is excessively unpleasant, resembling that of the compound formed by carbonic oxyde and chlorine. When it is merely brought in contact with certain combustible matters it

See Annals of Philosophy, 1813, and Phil. Transactions, 1812.

explodes

explodės violently, even without increasing the temperature. Its explosion is excessively violent when it touches phosphorus or phosphorised alcohol; but it has no effect on muriatic or sulpkuric acid, on zinc, tinfoil, or sulphur. The danger attending every process of analysis or combination has, perhaps, occasioned some degree of obscurity as to several of its properties; there can be no doubt, however, that its constituent parts are chlorine and azote. : With carbonic oxyde chlorine forms a peculiar compound to which Mr. John Davy has given the name of phosgene gas. When equal volumes of these substances, well dried, are mixed together in an exhausted gas receiver with a stop cock, and proper means used to exclude moisture, and thus exposed about a quarter of an hour to bright sunshine, the colour of the chlorine disappears; on opening the stop-cock over dry mercury, an absorption of one-half of the original bulk takes place, and the remaining gas is the compound mentioned above. It is extremely pungent and suffocating, and 100 cubic inches of it. weigh 105-97 grains.

Chlorine also combines with sulphur when it is passed over what is called the “ flowers of sulphur.” This compound is also obtained by heating sulphur in a retort filled with chlorine. It is called by Sir H. Davy sulphurane, on the ground formerly alluded to. · We have just time to add, that chlorine combines with phosphorus, and forms salts with sodium and potassium, the one the dry muriate of potash, and the other the muriate of soda.

We now come to jodine, on which we shall not long detain our readers. It has been already observed, that this is a substance very analogous to oxygen and chlorine, and that uo method.. baş yet succeeded for its decomposition. The following notices relative to it are abridged from the Philosophical Transactions for 1814.

“ Iodine absorbs chlorine, and forms a solid volatile substance of a yellow colour. When this compound dissolves in water, it forms an acid, to which the name of chlorionio acid has been given.

6. When heated in oxygen gas, or brought in contact with redhot hyperoxymuriate of potash, iodine undergoes no change. When it is passed over hot potassium, that metal burns with a pale blue flame; no gas is given out, but a white substance is formed soluble in water, and fusible at a red heat. .

" Iodine combines very readily with phosphorus, producing heat without light. When the iodine is in excess, a red volatile solid is produced : when the phosphorus is in excess, the compound is more fixed. An acid gas evolved during the combination, absorb

. able

able by water and by mercury, is called hydrionic acid, as being a compound of iodine and hydrogen.

“With potash and soda iodine readily combines, forming with each two saline compounds; the first, composed of oxygen, iodine, and the alkaline base, is analogous to the hyperoxymuriate of potash; the second is more soluble, and is a compound of iodine and the metallic base of the alkalies. Similar compounds are obtained of iodine and barytes, and probably of all the alkaline earths.

“ Iodine, when passed in the form of vapour over red-hot potash, expels oxygen. Chlorine, on the other hand, sets iodine free from almost all its compounds. In general, however, it is driven off from phosphorus and sulphur by oxygen.

• When put into ammonia, iodine forms a black powder, which detonates when dry. This, according to Sir H. Davy, is a compound of iodine and azote. Mercury absorbs nearly three-fourths of its weight of iodine. The weight of an atom is about 11. 75."

As soon as the progress of discovery had led chemists to suspect that oxygen is not the only supporter of combustion, and the sole principle of acidity, it became requisite no longer to employ a language which involved in all its expressions a doctrine apparently inconsistent with facts. Sir H. Davy, as we have already mentioned, constructed a system of terms whereby to de note the combinations of chlorine with the metals, sulphur, phos phorus, and some others. The principle upon which he proceeded was to change the Latin termination of the substance combining with chlorine into ane when the combination was confined to one proportion, and to substitute the syllables anea, when it was intended to express the second state, or greater de. gree of acidity. Dr. Thomson objected to this view of a supplementary nomenclature, preferring the obvious method suggested by the present usage of the Lavoiserian school; and as chlorine is avowedly analogous in its properties to oxygen, we can see no good reason for departing from the principle on which these properties are so admirably denoted and graduated. Instead, therefore, of phosphorane, this ingenious writer recommends chloride of phosphorus, and instead of argentane, chloride of silver. When there are two proportions in the combination, Dr. T. makes use of the prefires pro (for proto) and per: thus instead of stannane and stannanea, he says prochloride of tin and perchloride of tin. Nothing, however, is yet decidedly fixed on this important subject, and it cannot fail to be extremely puzzling to a beginner in the science to find the same thing under three or four different names. Thus common Table salt will meet his eye, first as muriate of soda, next as sodane, and lastly as chloride of sodium; and, what is peculiarly unfor, tunate, every turn of expression here involves a theory. From the brief sketch we have presented of the state of opi.

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nion among chemists, it must be very evident, that the princi. · ples of their science are quite unhinged. The beautiful and

compacted system of the French school has fallen down into a mass of disjointed facts. Chaos has returned; the light is again mingled with the darkness, and the work of the sixth day more than of the first, is without form and void. The doctrines which respected affinity and combustion were apparently the best established in the whole science: they were the pillars of the temple. Chemistry was regarded as a great work at unity in itself; it was named as a model for all other scientific pursuits. Physics could boast of nothing so complete in any other department. Astronomy bas its comets; but chemistry seemed to have no anomaly, no eccentric phenomena. It was, in short, at once the best 'specimen of natural philosophy, and of a rational logic.'

Amid the ruins of this fair system, however, let us repeat our satisfaction at the bold and unfettered spirit of liberty which every where pervades modern science. The influence of authority has passed away : and, in these times, we have seen a tower of strength fall to the earth in a moment, which, in the days of our forefathers would have imprisoned the human mind for ages. The truth of nature alone commands reverence now; and that alone is deemed fair and precious, which bears examination, and approves its consistency with fact. --Much remains to be done in this wide field, but the labourers are able, and their industry slacks not.

This recalls to our memory the labourers whose names stand at the head of this article. It was impossible to enter upon a regular review of their books, for the one is the supplement to a dictionary, and the other treats of every thing that will help to fill up a page. We are aware that Mr. Parkes is a chemical manufacturer, and therefore can have no fault to find with him for making books on chemistry. If his essays sell, however, we must congratulate him on having found a more potent agent than the famed desideratum of the alchemists; he can turn paper into gold. Is it the love of science that produces such books Pshaw!

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Art, VỊ. De la Littérature du Midi de l'Europe. Par S.C.L

Simonde de Sismondi, &c. &c.

· (Concluded from our last, page 49.) THE origin of the tales recorded by the Romance writers, nay, the origin of the composition itself, which we now call Romance; must be deduced from the tourpaments and justs, which was, for

: a long

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