public feemed the greatest of all poffible evils. On the other hand, the court of Verfailles were fenfible that the Dutch, who now relied folely on them for fupport, would, by fubfcribing to the league, become in a great meafure dependent on the emprefs; and it was by no means their intereft to renew at St. Petersburg a conteft for influence, which had already been decided in their favour at the Hague. From thefe concurrent caufes, notwithstanding the clamours of the Amfterdam merchants, the acceffion of the republic to the neutral league was delayed till after the commencement of hoftilities: it then acceded as a belligerent power; and was confequently precluded from thole advantages which were enjoyed by the neutrals.

The prince of Orange was now entrusted with the conduct of a war which he had long foreseen and deprecated, but to which, from a perverfe and untoward coincidence of events, he was by many confidered as acceffary. Convinced that the fyftem purfued and recommended by William the Third was founded in the trueft political wildom, that a union of the maritime powers was effential to the general balance of Europe, and that an intimate alliance with Great Britain was neceffary to the welfare of the republic, he had openly expreffed his predilection for the English at the beginning of the American quarrel. To this conduct the patriots now very artfully reverted. They accufed him of having advised the aggrettion of the English, and of contributing to their fuccefs by treachery. The evident inequality of the ftruggle, the notorious deficiency of all warlike articles in the dock-yards and arfenals of the republic, the frequent and public reclamations made by the prince and by the council of itate on the fubject of that deficiency were forgotten; and the wilful mifconduct of the fladtholder was boldly alledged by the patriots, as the fole caufe of that miferable feries of defeat and difgrace which immediately followed the commencement of hoftilities. Thefe allegations were not only published by patriots, and by the wretched libellitis in their pay, but were folemnly iffued from the pulpit. The priests indeed were, in every part of the republic, the most formidable of the fladtholder's opponents: from their mouths no falsehoods were found too grofs for belief; and they thought none too abfurd for affertion."

It is the opinion of this author, that, whatever predilection. the ftadtholder had for Great Britain, the charges brought against his general conduct, during the war, appear to have been not well founded.-We cannot difmifs this work without obferving, that it is written with a propriety, a chaftenefs, and energy of style, which merits our commendation.

Memoirs

Memoirs relative to the Campaign of 1788, in Sweden. By bit Serene Highness Prince Charles of Heffe, Commander in Chief of the Danish Auxiliary Army. Tranflated from the French, with thirty-three Vouchers. 8vo. 35. 6d. Baldwin.

THE HIS production may be confidered partly as a manifesto of the court of Denmark, with refpect to its conduct in the late hoftilities against Sweden, and partly as a defence of prince Charles of Heffe, from the imputation of being a fpy, in his paffage through the latter of these kingdoms to Norway, a short time previous to the rupture between the two crowns. The following extract, however, contains the offenfible motive, affigned for the publication by his ferene highness:

The different opinions of the public, fays he, concerning the entry into Sweden of a corps of Danish or Norwegian auxiliaries, ceded by the king to her imperial majesty of Ruffia, are an evident proof, that people even in other refpects well informed, have not been thoroughly fo of the affair in question, nor its confequences. The reports and infinuations of the oppolite party, and the erroneous articles which fwarm in the newspapers, have occafioned falfe interpretations of the moft natural things; and made the conduct of the court of Denmark, its all ance with Ruffia, and the movements and behaviour of its troops in Sweden, to be confidered in a wrong point of view. I think it incumbent, therefore, on me to give the pub. lic, Denmark, and myfelf, a fuccinct account of this event, and its caufes."

We must acknowledge we are not perfectly satisfied as to the propriety of a perfon's giving an account of any transaction to kimfelf. But waving this objection, fince it is the fortune of few characters to be crowned with both Minervas,' we readily give the prince credit, for what he fubjoins refpecting his veracity.

An ingenious freedom, continues he, which forms the ba fis of my character, fhall guide my pen; and I will conceal from the public only fuch facts as might injure, or bring fhame on, fome perfons, without leading to the end I propose.'

As the fubject of these Memoirs can afford but little gratification to our readers, it is fufficient for us to obferve, that the account given by prince Charles is favourable to the honour of the court of Denmark; and that the truth of the narrative is fupported by a number of written documents, of various kinds.

FOREIGN

FOREIGN LITERARY INTELLIGENCE.

intelligence of the various additions made to the flock of scientific knowledge, we are obliged to truft for the labours of English philofophers to the delay of a feparate publication, or to the appearance of each number of the Philofophical Tranfactions, where, from various caufes, many difcoveries cannot appear. We have, on this account, been compelled, at different times, to add the attempts of our countrymen to those of foreigners, because we have firft collected them from the foreign journa's, a method difgraceful to a scientific nation, who ought. to have fome periodical work to record their various labours in the literary department. We purpose, as far as we are able, to remedy this inconvenience; and will give an early account of any scientific communications which we may receive immediately from the author, or from any perfon commiffioned by him. We fhall occafionally interweave them with the subjects of this sketch, or, if we are employed on a different one, thall add it to our Number, under the title of Domestic Intelligence. It will depend on the communications we may receive, whether we can regularly add a few pages in each Review, under the latter title. This propofal, fuggefted by the appearance of Mr. Willis' and Dr. Blagden's difcoveries in a foreign journal, will, we hope, be examined with candour; and not rejected by philofophers, who will derive the chief benefit from the communication our readers alfo will undoubtedly be gratified by fuch early information. But we fhall foon take another opportunity to explain this plan.

Dr. Blagden's obfervation is a fingular one. Alkaline and pure air, after paffing through a red-hot tube, produced nitrous air. The phlogifticated part of the alkaline air joined with the oxygen to make nitrous air, while the inflammable air, with the rest of the oxygen, formed, according to M. Sennebier's obfervation, water. But we fee no neceffity for this new combination. The inflammable air was in part diffipated in light and heat, and the new body requised the other ingre dients: the pure air must be in excess.

Mr. Willis has been employed in fufing platina with fuc cefs; but there are fome peculiarities ftill in this metal which we cannot explain. He fufed it by wrapping it in paper, and placing it on a bed of charcoal finely powdered: the quantity of charcoal must not, he thinks, be very great: to an ounce of the metal he adds a drachm of alkali of tartar, two drachms of borax, and a drachm of powdered charcoal, The fufion was complete, but he was not always equally fuccefsful: and, when the metal was fufed, it was found not to be malleable. The French tranflator thinks, that it was fufed in confequence of the remaining iron: if entirely free from iron, VOL. LXVIII. Dec. 1789.

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it would, he obfcrres, agglutinate and become malleable; but this opinion feems to be contradicted by Mr. Willis's 13th ex périment. Our author alfo could not procure malleable platina by Mr. Pelletier's method, viz, by firt fuling it with the phofphoric acid, and next with charcoal: he futed the metal, but it was too harsh and brittle. The specific gravity of the platina was from 15.353 to 16.5; and the heat required to fufe it was, at leaf, 150° of Wedgwood's thermometer, about 20377° of Farenheit's, according to Mr. Wedgwood's own comparifon.

We may now follow the fame fubject from authors really foreign. Gold we know to be nearly connected with platina, and we find gold has been discovered in fome of the galenæ of France. Galena generally contains about 67 parts of lead, 24 of calcareous earth, and about 9 or 10 of fulphur. That which rifes near Aulas in the Pyrenees produces 60 pounds of lead from a quintal of the ore, and 3 ounces of filver in a quintal of the metal. In the filver, a fufficient quantity of gold was discovered to deferve feparation on a large fcale. Native gold and filver often occur in a matrix of calcareous spar and galena, particularly in fome rich mines of Siberia, where above a third of gold has been found in native filver. M. Sage has compared the red mineral filver from Peru with that of the mine of St. Mary: each are in colour the fime; but that of Peru is ten times richer in filver than the other: the latter contains 78 parts in 100 of arfenic. The water and mephitic acid are in fimall quantity, and nearly in the fame proportion, in each. Mercury, we are told by M. de la Roupe, may be recovered by pouring æther upon it. The calx changes into a greyish powder, but it affomed its metallic form only when dried by heat, and firred with a knife. The ather undoubtedly furnished much of the phlogiston.

The art of whitening copper or brafs by means of tin has been hitherto little underflood, either in the practice or its theory: the latter we cannot clearly perceive: but the former we fhall fhortly explain from the memoir of M. Gadolin, read to the academy at Stockholm; the remarks on it by the baron Gedda; and the anfwer of profeffor Gadolin, which lie before us. But it is neceffary to premife, that, in England, tinning has two different meanings. Our copper kitchen utenfils are covered with lamine of tin melted in the vessel previ oufly heated, and prepared by mixtures which are supposed to open the pores of the copper, and facilitate the union of the metals. The union, however, chiefly depends on thefe metais being fitted to each other in a heated flate, and contracting on each other when cold. The preparation chiefly of crude fal ammoniac, and fome other ingredients, feems ufeful only in preventing the calcination, or diffolving the calx. Another method of tin. ning or whitening brafs is that employed in the pin manufac, tory, which is, at leaft was, kept as the profoundeft fecret; and

a third:

a third the tinning of iron plates, to form what was formerly called latten, has been known, we believe, ever fince the days of Reaumur. The English improvement confifts, we apprehend, in palling them through a rolling mill: but the thin coat of tin, depofited from a menftruum on the polifhed brafs chiefly employed in making pins, blanching nails, tenter hooks, the bits of horfes, &c. is our object of enquiry at prefent. In this procefs, the calx of tin is diffolved in the acid of tartar ; but the mode of effecting the precipitation which apparently takes place, without a previous diffolution of the metallic tin, is the great difficulty. Our author found, that the copper could not feparate tin in a metallic form unless fome other tin, in the metallic form, was in the folution. The blanching (we must beg leave to use a term already naturalized in the practice of the art) he obferves, fucceeds beft, if the copper is boiled with the metallic tin in a folution where the acid is a little in excess, and with this precaution only, a fmall proportion of the tin is precipitated; but if the acid is greatly in excefs, or is entirely faturated by the tin, the experiment fails. A little iron, recently diffolved in the acid, does no injury to the colour. The tin feems to be diffolved more copiously in tartar or its acid, if a calcined calx of tin is previoully combined with the folution: if the calx of copper is first diffolved in the acid, the pellicle of tin is of a dirty colour.

The baron de Gedda, in his remarks on this paper, obferves, that alum and common falt, or either alone may be employed, instead of tartar, in the procefs of blanching; but common falt alfo diffolves a little of the copper, and injures the white colour. If the copper and tin are put in together, a little of the copper feems to be diffolved, and the colour to be injured; but if alum is employed, they may be added at once without danger. The neceflity of the prefence of tin, in a metallic state, are fully evinced by the baron; but he doubts whether the experiment will not fucceed as well, when the acid is faturated : he doubts too, whether, when the tin is wholly diffolved, and the colour depofited is blackifli, on account of the folution of copper, fresh tin will not render the fame folution fit for blanch ing.

M. Gadolin, in his answer to the baron, fhews, that gold may be blanched in this way, though it is not foluble in the menftruum; and concludes, that the blanching wholly depends on the attraction of the copper for tin in its ftate of a metal, which the baron had doubted. Iron, in a fimilar procefs, was covered with tin, though not of a bright colour; but a little iron feemed to favour the precipitation on the copper, particu larly when a folution of alum was employed as the menftruum. When the blanching power of the menftruum is loft by a folution of copper, it may be recovered by precipitating the copper. If a polifh is wanted rather than a more perfect blanching, tartar is the best menftruum. Alum gives a very perfect whitenefs

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