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A Chemical Analysis of Wolfram; and Examination of a nerv Metal, which enters into its Compofition. By Don John Joseph and Don Faufto De Luyart.' Tranflated from the Spanish by Charles Cullen, Efq. 8vo. 15. 6d. G. Nicol.

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WE E are much pleased to see this ray of true science dawn in Spain: the analysis is executed with great accuracy and addrefs; and thefe pupils of Bergman feem not to have been corrupted by the indolence, ufually infpired with the Spanifh air; or the example of their countrymen. In our laft volume, page 274, we extracted from Mr. Kirwan's work, the properties of the tungstein acid, as they appeared both to Bergman and Schele; fo that we need not make any particular obfervations on the introductory analyfis of thefe chemifts, which are properly prefixed to the prefent tranflation. We hall only premife, that the tungftein itself is easily diftinguished from all stones; for, when the marine acid is poured on it in powder, and the mixture is fet in a digefting heat, the powdered stone acquires a fine light yellow colour.

In the moist way, 100 grains of wolfram are found to confift of 22 of a black calx of manganefe; 13 of a calx of iron; 65 of a yellow matter; and 2 grains of a refiduum, confifting of a mixture of quartz and tin. The flight increase of weight may proceed from the calcination of the iron and manganefe; fince the fum of all these quantities amount to 102 grains.

The nature of the yellow matter was next to be examined; and it appeared, in particular circumstances, to form the acid of tungtein of Mr. Schele; but not to be a pure uncompounded fubftance, as he fuppofed, the finall quantity of his materials having prevented him from pursuing the analyfis with his ufual accuracy. The meffieurs Luyarts diffolved this yellow matter in the cauftic alkali, and precipitating it again by an acid, procured a falt, fharp and bitter to the tafte, which continued to be foluble on the flighteft agitation, while any of the alkali was fuperabundant. This falt, compofed of fome alkali, the precipitating acid, and the yellow matter, was that to which the Swedish chemists had given the title of acid of tungstein Thefe details explain the caufe of the appearances of acidity in the radical basis of the tungstein, and of its diftinguishing quality with the marine acid. It is actually found to be a metallic calx, as Bergman fufpected, and has been reduced by these authors, by means of charcoal alone: we shall extract their very fhort account of the appearances of the metal, which at prefent feems very refractory.

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Having put another hundred grains of this powder into a Zamora crucible, provided with charcoal, and well covered, and placed it in a strong fire, where it remained an hour and a half, we found, on breaking the crucible after it was cool, à button, which fell to powder between the fingers. Its colour was dark brown; and on examining it with a glass, there was seen a congeries of metallic globules, among which fome were the bigness of a pin's head, and when broke, had a metallic appearance at the fracture in colour like steel. It weighed fixty grains, of course there was a diminution of forty. Its Specific gravity was 17,6. Having calcined part of it, it became yellow, with increase of weight. Having put one portion of this fubftance powdered, in digeflion with the vitriolic acid, and another with the marine acid, neither of them fuffered more diminution than of their weight; then decanting the liquor, and examining the powder with a glass, the grains were still perceived of a metallic aspect. Both the acid liquors gave a blue precipitate with the Pruffian alkali, which let us know that the small diminution proceeded from a portion of iron which the button had undoubtedly got from the powder of the charcoal in which it had been fet. The nitrous acid, and aqua regia, extracted likewise from two other portions of the ferruginous part; but besides they converted them into yellow powder, perfectly fimilar to that which we ufed in this operation.'

The acid nature of the calx now appears equivocal; but the authors are seemingly anxious for the reputation of Bergman, and eager to establish the general acid nature of metallic calces. But, though they own that they have not been able 10 obtain it pure, with properties decidedly acid, yet the union of the calx with alkalis, and particularly with the volatile alkali, as well as the properties of the compounds, show, in their opinion, that it is of an acid nature. These appearances seem however to us, very equivocal; but experience, rather than reasoning, muft ultimately decide. It is more clear, that this metallic fubftance should be arranged with the other metals; and that it poffeffes diftinct and permanent properties. Mr. Kirwan has added the wolfram to the fpecies of iron ore, but has claffed it with those of an uncertain nature. The analysis, which he extracts from Lehman, fuppofes it to confist of quartz, calx of iron, and a small proportion of tin. Mr. Kirwan adds, that from the experiments, he fufpects it to contain manganefe alfo. We do not mention this to detract from that excellent work, for it can never be perfect while any thing remains undifcovered; but merely to show what had

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been already done, and how much our authors had performed.

The memoir is written with accuracy, and feems to be tranflated with fidelity.

Rhetorical Grammar, or Courfe of Leffons in Elocution. By J. Walker. 12mo. 35. 6d. Robinson.

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'HE defign of this work is, to give young perfons an idea of the principles of fpeaking and reading with propriety. If these principles feem to be a little abftrufe, it must be confidered, that it is an arduous talk to investigate the various powers and properties of the human voice, and to difcriminate the precife tone, air, and energy, with which a sentence ought to be delivered. We daily feel in ourselves, and observe in others, the difficulty of pronouncing a page, either in verfe or profe, with a juft and graceful elocution. That there is a real difficulty in the acquifition of this art, must be acknowleged by every one who confiders what a small number of good fpeakers we have, either on the ftage, at the bar, in the fenate, or in the church. Yet furely there is no part of edu cation which deserves to be more attentively studied than the art of speaking. It will amply repay our utmost exertions. An harmonious voice, which may be improved, if not acquired, by exercife and habit, is extremely pleafing, both in Speaking and reading. It gives weight and energy to every word; it captivates the ear, penetrates the foul, and even adds an irrefiftible charm to beauty.

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The ingenious author of this Rhetorical Grammar has taken uncommon pains, not only by his publications, but by his perfonal inftructions, to improve the fate of our public elocution. In the prefent courfe of leffons, he feems to have reduced his whole theory into one complete and practical fyftem. And he very reafonably hopes, that the fentences adduced for the illuftration of the rules, the direction for the pronunciation of the figures of rhetoric, and above all, the praxis at the end, will be found the most certain, and at the fame time the most easy, method of acquiring the art of reading, that has hitherto been offered to the public.

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The first part of this Grammar confifts of instructions, addreffed to parents and teachers of elocution. Here the author very properly obferves, that it is a grofs, as well as a common miitake of parents to fuppofe, that it is of little confequence who is employed in teaching a child the firft rudiments of reading. This naturally leads him to point out some of the principal faults in the pronunciation of the younger class of VOL. LIX. Feb. 1785.

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pupils ;

pupils; in founding the vowels too flightly, in pronouncing s indiftinctly after ft, in pronouncing w for v, and inversely, &c. in pronouncing too rapidly, and in reading with a menotony.

In some of his introductory leffons, he endeavours to afcertain the true found of the auxiliary verbs, and other words of common occurrence; and then gives his young pupils a general idea of the common doctrine of punctuation; and more especially of what he calls rhetorical punctuation, namely, the nature and use of paufes.

. A very effential part of the theory laid down in his Elements of Elocutions, confifted in the discovery and illuftration of two principal inflections in the human voice, which he calls the rifing and the falling flide. In this treatife he explains and exemplifies thefe inflexions. And in anfwer to any objection which may be alleged against this part of his Grammar he fays:

So little has the fpeaking voice been ftudied, and fo little are children practifed to diftinguish between fpeaking founds, that the author will not be surprised, if neither the teacher nor pupil can at first perfectly comprehend the nature of the two lides, on which fo much of his fyftem depends; but, as this fystem obliged him to bring together every kind of fentence, and to clafs them according to their feveral diftinguishing properties, he flatters himself that by reading fentences thus claffed and arranged, the pupil will find more benefit, than by any other method yet difcovered, even if he does not understand the different flides of voice, which are here annexed to them." In the following fection he thus explains the nature of thefe inflections:

The human voice, like all other founds, may be confidered as divifible into high and low, loud and foft: we may dwell a longer, or a fhorter time, upon each of thefe varieties, and they may fucceed one another, either more rapidly, or more flowly. These feem to be all the radical diftinctions of founds in general, but these may all be applied to mufical founds. Speaking founds, to all thefe diverfities, add another; which is, that of fliding up and down the scale of founds by infenfible degrees, exactly like the found produced by a violin, when the finger flides up and down the string, while the bow vibrates it; fo that fpeaking founds may not be improperly called a fpecies of chromatic mufic. Thefe founds, however, are in general fo rapid and initantaneous, the flides fo fhort, and the difference between them fo fmall, as fcarcely to be perceptible. We hear a variety upon the whole, but we cannot arrest it for examination. But when we read or fpeak deliberately, we perceive the flides more diftin&tly; and if we drawl out our words, they become very apparent: if a word requires a strong

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emphafis, and we dwell fome time upon it, efpecially if the word ends with an open vowel, we find the voice flide either upward or downward very perceptibly. Now, what the voice is heard to do when pronouncing flowly or forcibly, it certainly does when pronouncing rapidly and feebly, though the flides are not quite fo perceptible: for if this were not the cafe, we muft neceffarily hear either a monotone or a fong; as it is in flides only that thefe differ from fpeaking founds.

"If then fpeaking founds are slides, and these flides are neceffarily either upward or downward, farely it is of fome importance to the art of speaking to be acquainted with them. By understanding thefe flides, we can tell a pupil, not only that he is too high or too low, too loud or too foft, too quick or too flow, but that he makes use of an improper flide, a fpecies of instruction as neceffary as any other; but for want of studying the human voice, is totally unintelligible to him. Let us fuppofe, for example, a youth but little inftructed in the art of reading were to pronounce the following fenterice :

"Though we have no regard to our own character, we ought to have fome regard for the character of others."

There is the greatest probability I fay, fuch a reader would pronounce the firft emphatic word own with the rifing, and the Laft emphatic word others with the falling inflexion, though this pronounciation certainly does not bring out the strongest fenfe of which the fentence is fufceptible. To tell him he must lay more ftrefs upon the word own will by no means fet him right, unlefs he understands the peculiar kind of ftrefs to be given; for he may increase the ftrefs upon both the emphatic words without in the leaft removing the impropriety. But if his ear were fufficiently acquainted with this diftinction to lay the emphafis with the falling lide on own, and that with the rifing ide on others, a new and forcible meaning would be ftruck out, and the importance of these flides fully exemplified.'

The author proceeds to fhew the method of acquiring a knowlege of thefe flides, and to exemplify their ufe and application in fentences of every fort.

The fubfequent part of this Grammar contains an explana tion of the figures of rhetoric, with directions for the proper manner of pronouncing them. We fhall give our readers, as a fpecimen, our author's obfervations on irony, which perhaps of all the figures in rhetoric requires the greatest art and attention in the modulation of the voice.

Irony is a figure, in which one. extreme is fignified by its oppofite extreme; or where we speak of one thing and defign another, in order to give the greater force and poignancy to our meaning. Thus Cicero fometimes applies it in the way of jeft and banter, where he says,

We have much reason to believe the modet man would not ask him for his debt, where he purfues his life." Pro Quint. c. 11. 7

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