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and was universally hailed as a deliverer. * They compare the domestic squabbles of the Carthaginians, when their very existence was threatened from without, to our scruples about the Royal conscience, and our fears about the established Church, when the enemy is thundering at our gates. In their mind, there is no surer prognostic of our doom, than the strange policy of suffering our internal sores to fester and imposthumate,-of distilling immunities, drop by drop, to a clamorous and discontented people,-as if it were actually our policy to quicken their relish, and to embitter their resentments.
Overweening as those anticipations are, it is lamentable to think how broad a foundation they have in fact. We have a fleet; indeed, and a population very different from that of Carthage. But Ireland is a vital member of our empire, and not a distant dependency like Spain. A dreadful crisis, we have no doubt, is preparing for us; and how are we prepared to meet it? We have substantially means for a noble struggle-we think, for a sure defence ; but they are locked up by prejudice, by faction, and by base and shortsighted self-interest. The near approach of the most tremendous danger which ever threatened any nation in the annals of the world, has made no change in our feelings, nor, ,' so far as we can observe, in our policy. The same want of system,--the same blustering series of paltry expedients,—the same headstrong rashness and ignorant confidence, which have proved the ruin of the kingdoms around us;- are still manifest, we are afraid, among ourselves. Is there any reasonable creature who, can hear the name of Ireland pronounced, and think what may be its situation before another year has gone over us, without consternation and dismay? Yet no step is taken to allay the discontents of the Irish ; and court-interest, and place and preferment, are still sought after by the same system of mean compliance and angry recrimination, by which court affairs may be well enough conducted in times of security and peace. At such a season, we should disdain to think of party, or to waste a word upon the comparative merits of ministers, or of their opponents. We want to see the real strength and resources of the nation applied to the task of its deliverance; and we care not by what hands this great object may be effected. The place of a British minister, indeed, does not to us, at this moment; appear an object of attraction or envy. Even to the most powerful ta-,
* There is a melancholy exactitude in some points of this comparison. Those who require to feel the full force of the example, will do well to consult the 6th chapter, 10th book of Polybius, wherein he narrates the alarms of the Carthaginians, and the conduct of the Spaniards, on the approach of their invaders,
lents and the most exalted virtues, it must be environed with depressing anxieties, and tremendous responsibility. Incapacity, indeed, is generally insensible of the dangers which it is sure to enhance; and selfishness is, for the most part, as rash as it is ultimately cowardly. .
Of peace, we are afraid, it is now useless to say any thing. The time for that sage and cautious policy is probably irrevocably passed over. It might have saved Europe, long after the consequences of the opposite system had become manifest : but Europe is lost; and the condition of England is no longer what it was. Our enemy is not likely to grant us peace, and it is more than doubtful if we could accept of any terms which he would offer. We hope, however, that no one is still found so insane as to expect that we shall force him to an accommodation by the commercial distress of his dominions. He does not want commerce. His armies suffer nothing from that distress; and he cares nothing for the discontents or privations of the millions he has reduced to slavery. This weapon, åt all events, will unquestionably recoil on ourselves ; and the eagerness with which the enemy has taken advantage of our decrees, to seal up hermetically almost every port on the Continent, demonstrates how truly those decrees have actually seconded his designs.
When we look stedfastly on the power which we have endea. voured to describe, and on the measures and the councils by which it has hitherto been opposed, we confess that we cannot be sanguine ;, and that we cannot be satisfied. We shall be called Jacobins and friends of Bonaparte, we suppose, for expressing these sentiments. This is to us a matter of perfect indifference. We do our duty in making public the facts and the impressions to which we think it of importance that the attention of the country should be directed ; and are too much occupied with the honest anxiety excited by these statements, even to be conscious of the contempt with which, at another time, we might treat such insinuations.
Art. X. Electro-Chemical Researches on the Decomposition of
the Earths ; with Observations on the Metals obtained from the Alkaline Earths, and on the Amalgam procured from Ammonia. By Humphrey Davy, Esq. Sec. R.S. M. R. I. A. (From the Philosophical Tranfactions for 1808, Part II.)
T e had the fatisfaction of introducing to the knowledge of
our readersin two former Numbers, the ingenious and elaborate firies of experiments by which Mr Davy was led to the
discovery of some new properties of electricity, and, by their means, to the decomposition of the fixed alkalis. These discoveries, by far the most striking for their novelty, and the most important for the further views which they open, of any that have been made since the new theory was established, have attracted the notice of chemical inquirers in this and in other countries : and, although the miserable state of public affairs has prevented them from exciting so general an interest, and producing as large an harvest as they must have done had they fallen on happier times, a considerable progress has nevertheless been made, both by the disa coverer himself and those whom his successful researches set in motion, even during the short interval which has elapsed since we last brought the subject under review. The chemists of France have most unexpectedly found that the decomposition of the alkalis is much easier than was at first imagined, and that it may be effected by other ways than the electric agency. The Swedish philosophers have accomplished a discovery yet more surprising-perhaps, of all the late results, the most unlooked for the metallic nature of ammonia, and consequently of the two gases which constitute that alkali.' Mr Davy has, in the mean while, pursued his brilliant course of investigation with almost uninterrupted success, and has added, to the knowledge which he formerly gave us of the fixed alkalis, that of the principal earths. The decomposition of these bodies being attended with greater difficulty, and requiring a more complicated and powerful apparatus than is neceffary for the resolution of the alkalis, our author has not brought all his expea riments to what he deems the utmoft pitch of accuracy and preci.. fion. But, because he sees no prospect of soon obtaining the requisite machinery, he most wisely and meritoriously gives them to the world in their present state, preferring,' to use his own ex. pressions, the imputation of having published unfinished labours, to that of having concealed any new facts from the scientific world,
which may tend to aslift the progress of chemical knowledge.' · We certainly do not mean to detract any thing from the praises
due to such disinterested conduct, when we say that Mr Davy can abundantly afford to share his ample revenue of discoveries with his less fortunate brethren. · The galvanic battery being applied to lime, strontites and barytes, in the same manner as it had been to the alkalis, a decomposition was observed to take place. Gas was evolved, and metallic globules were produced in contact with the negative wires. But this process could not be completed so as to show the nature of the products in a satisfactory manner. Potassium.(the basis of potaih) being heated in contact with alkaline earths, seemed to act upon them; but this experiment did not appear to eifcet their decompo
fition. Mixtures of potash with the same earths, acted upon by the galvanic battery, showed signs of decomposition. Metallic bodies were produced less fusible than potassium, burning immediately after their formation, and reproducing the mixture of alkali and earth employed. But much more satisfactory results were obtained by exposing to the battery mixtures of the earths and metallic oxides. The presence of the metal greatly assists the operaa tion; and an alloy is produced at the negative point, consisting of the metal reduced, and the metal of the earth likewise freed from its oxygen. The alloy, when exposed to air or water, reproduces the earth by oxygenation ; but still, from the proneness of these new metals to unite with the wires of the battery, and to burn almolt as soon as they were formed, sufficient quantities could not be obtained for the purposes of examination ; and our author was engaged in repeating and varying his attempts to effect the decompofition more easily, when he received a letter from Professor Berzelius of Stockholm, stating that he and Dr Pontin had completed the process with great eafe, by exhibiting negatively electrified mercury to barytes and lime. Mr Davy repeated this process with signal success'; and he does not withhold from it the praise which its ingenuity deserves. He applied it likewise to strontites and magnesia; with the former, it succeeded more eally than with the latter :--but, in all these cases, an amalgam is formed of mercury with the metallic basis of the earth; and this amalgam again gives earth and mercury, when exposed to the air or to the action of water. The process he found to be greatly facilitated by using muriates or fulphates of the earths, instead of the simple earths.
By combining this method of the Swedish chemists with his own, formerly described, Mr Davy obtained, in considerable quantities, the amalgams of mercury and the bases of the earths. He placed on platina a mixture of the earth and oxide of mercury ;in this mixture he made a cavity, wherein he poured a globule of mercury-and, covering the globule with a film of naphtha, he made the platina positive, and the globule negative :--it was fpeedily converted into the amalgam required. This was exposed to Itrong heat in a glass tube, in order to expel the mercury; but our author scarcely ventures to assert that he ever completely succeeded in separating the two substances. He seems to have come nearest his object in the case of barytes, and to have failed most with lime. Of none of these metallic bafes did he obtain a fufficient quantity for a satisfactory examination of their physical and chemical properties. They seem in general to resemble one another ;- they are solid, except at high temperatures ;-they are much heavier than water,-have a high metallic lustre, resembling
that that of filver ; and require a considerable force to flatten them. When exposed to oxygen, they absorb it greedily, and return to their native earths respectively. "These new substances,' says Mr Davy, 'will demand names; and, on the same principles as I have named the bases of the fixed alkalies, potassium and sodium, I shall venture to denominate the metals from the alkaline earths barium, strontium, calcium, and magnium. The last of these words is undoubtedly objectionable ; but magnesium has been already applied to metallic manganese, and would consequently have been an equivocal term.'
Our author next directed his inquiries to the constitution of other earthy bodies,-filex, alumine, zircone, and glucine, but with much less success. He pursued his experiments indeed with unremitting perseverance, and with his usual ingenuity; but, although he has related them at some length, and although the recital is highly valuable to future experimenters, we shall not follow it any further than to add, that there seems reason to infer that the earths in question have, like the alkaline earths, metallic bases; and we are confident Mr Davy's future refearches will both establish this point as satisfactorily as he has demonstrated the on ther, and will give us the same knowledge of the propertiesof the new bases.
The last object of research was suggested to our author by a very important experiment of the Swedish chemists, formerly mentioned. These ingenious philosophers found, that mercury, placed in contact with a solution of ammonia, and negatively electrified, expands in volume, and becomes a soft folid ;-that this folid, on exposure to air, absorbs oxygen, and reproduces ammonia and mercury ;-that water is decompounded by it, giving out hydrogen gas, and leaving solution of ammonia and mercury. The conclufion naturally drawn from this curious experiment was, that ammonia is, as Mr Davy himself had formerly supposed, an oxide with a double basis, composed of hydrogen and nitrogen ; but it seems to show also, that this double balis possesses metallic properties. So unexpected a light could not fail to attract the quick and discerning eyes of our author; and he lost no time in pursuing the track into which it plainly led him. His first repetition of the Swedish experiment suggested a very material improvement on it-the substitution of neutral salt of ammonia, whereby the deoxygenation and amalgamation are effected in the nascent state of that alkali, and are, consequently, more easily performed. His process was thus the same with that formerly described for deoxygenating the earths ; only, that instead of sulphates or muriates of those earths, he exhibited muriate of ammonia. "The acstion,' says he,' of the quicksilver on the falt was immediate.