derstood. Mr. G. has therefore attempted to put the matter in a more clear point of view, and in fome refpects with confiderable fuccefs. His hypothefis will not, however, in our opinion, explain all the phenomena of this kind of founds. At the fame time we must allow it to be extremely ingenious and interefting. We with much, that our limits would have permitted us to have prefented the reader with an analysis of the paper.

Art. 5. On the Benefits and Duties refulting from the Inftitution of Societies for the Advancement of Literature aud Philofophy. By the Rev. Thomas Gisborne, M. A. Communicated by Dr. Percival.-In the beginning of this interesting paper the author fuggefts a very difficult queftion, namely, what fituation is the most favourable for the inftitution of literary and philofophical focieties. He decides in favour of the metropolis and large provincial towns. If the point were, however, to be determined by the importance of the periodical labours of fuch inftitutions, the capital would probably be found not to have any great fuperiority over the provincial fituation. Each have their advantages, as well as their difadvantages; but the author has paffed by them with too curfory a notice.

The benefits to be expected from these affociations are described with much correctness and knowledge of the fubject; but in ftating the evils that may be produced by them, the writer has, perhaps, dwelled longer than was neceffary on the danger to be apprehended from political con

tention.

Art. 6. On an univerfal Character; in a Letter from James Anderson, LL.D. F.R.S. F.A.S.S., &c. to Edward Holme, M.D. The forming of a method of conveying our ideas, that could be univerfally underftood, has long been a defideratum with the learned. This Dr. A., Lowever, here fuppofes he has accomplished.

P. 90. I have,' fays he, at laft hit upon a device by which this difficulty can be totally removed; which is fo perfectly fimple, that it is inconceivable why it fhould not have been adopted many ages ago. This may be called a new art of writing. It is of fuch a nature, that two perfons inftructed in this art, though they ufe each a language that is totally unknown to the other, may correfpond with each other with much more facility than I can correfpond with you; and though each ufes his own language in writing, the other reads it in his own language. In short, the fame writing, were it fhewed to a multitude who used five hundred different languages totally unknown to each other, would be equally intelligible to the whole; and every individual would read it, and exprefs it readily in his own native tongue, provided he had been previously acquainted with this art. Nor would it be a matter of greater difficulty to learn this, than it is at prefent to learn to read and write one's native language.'

In explanation of this great difcovery he obferves farther, P. 91.

Suppofing a ftone were to fall from the clouds, with the characters 1795 delineated upon it; and that tone were to be exhibited to a convention of people, confifting of one of each of the nations of Europe, they would all read it with equal cafe, and understand it perfectly. If you asked an englishman what it was, he would answer, one thousand feven hundred and ninety-five, and that it denoted the prefent year of the Chriftian æra. Afk a frenchman, he would as readily anfwer, mil-feptCent-quatre-vingt-quinze. A fpaniard-a german-a rufs, &c. would

cach

each read it in the fame manner in his own language. Here then is all that I propofe to do:-it is merely to extend to words in general, what we now apply only to thofe words that denote numbers.'

This he thinks has, in fact, been done by the chinese for more than three thousand years past.

After finding means to overcome various difficulties, that prefented thenfelves in profecuting this fubject, the doctor goes on to tell us, that

P. 95. These characters can be formed in fuch an analytical way, as to be of even more eafy reference in a dictionary than the alphabetical . arrangement now in ufe; and printing might be practifed with half the number of types that are now required. I was perfectly aftonished at the facility with which all these things could be done; and not less pleafed on contemplating the benefits that would refult from this mode of writing, were it introduced into general practice.

The first advantage would be the opening of a free literary intercourfe among all nations; as the writings and books of every nation would be equally intelligible to all other nations as to thofe to whom they originally belonged.

The fecond would be facilitating the art of writing-for any man could then write as faft as another can speak; and the difcourfe would be taken down, not as it now is (by thofe who write it in fhort-hand) by half words and mutilated fentences, liable to be mistaken; but completely and entirely, with as much accuracy as if the orator had written it word for word with his own hand.

A third advantage would be a diminution of space in writing, and a ftill greater diminution in printing; fo that a fingle page might be made to contain nearly half a volume. This would greatly diminish the price of books, and confequently augment their circulation.

To these advantages I may add, that it would give a precision and accuracy of expreffion to written language that it never yet has attained, without neceffarily affecting the spoken language of any country. But I am fenfible that till it can be fhewn bow all this can be done, it is like putting down a parcel of enigmas to ftate them, though they will be perfectly obvious when explained. What would our forefathers, before the knowledge of the arabic numerals, have thought of a man who should have faid: that, by means of ten trifling characters, he could perform the different operations in arithmetic, which we know can be done with the utmoft eafe? He would have been nearly as much credited if he had faid: that, by means of ten little sticks, he could make a ladder on which he could afcend to the moon.'

A schedule of the fcheme, which contains the perfonal pronouns, is given by way of illustration.

7:

Art. 7. The inverje Method of central Forces. Communicated by Dr. Holme. This is given by way of addendum to a paper contained in a former volume. It's nature prevents us from giving any analyfis of it.

Art. 8. Obfervations on Iron and Steel. By Jofeph Collier-This is a valuable paper of the practical kind; and on a fubject of great importance. The modes of preparing good malleable iron have not been well defcribed, any more than the procefs of cementation for converting it into steel. The writer of this paper, therefore, endeavours to render thefe different operations clear and intelligible. The feveral methods of operating in forming iron, as practifed at Sheffield, are first detailed, after which the author comes to the cementation of it into fteel. The

furnaces

furnaces for making fteel, he tells us, are conical buildings; about the middle of which are two troughs of brick or fire-ftone, which will hold about four tons of iron in the bar. At the bottom they have a long grate for fire. They are not, however, eafily, understood without the plate that accompanies their defcription.

The furnace being thus prepared, the proceffes for different kinds of fteel are as follow.

P. 117. A layer of charcoal duft is put upon the bottom of the trough; and, upon that, a layer of bar iron, and so on alternately until the trough is full. It is then, covered over with clay to keep out the air; which, if admitted, would effectually prevent the cementation. When the fire is put into the grate, the heat paffes round by means of flues, made at intervals, by the fides of the trough. The fire is continued until the converfion is complete, which generally happens in about eight or ten days. There is a hole in the fide by which the workmen draw out a bar occafionally, to fee how far the tranfmutation has proceeded. This they determine by the blifters upon the furface of the bars. If they be not fufficiently changed, the hole is again clofed carefully to exclude the air; but if, on the contrary, the change be complete, the fire is extinguifhed, and the fteel is left to cool for about eight days more, when the procefs for making bliftered fteel is finished.

For fall wares, the bars are drawn under the tilt hammer, to about half an inch broad and three fixteenths of an inch thick.

The change wrought on bliftered fteel by the tilt hammer, is nearly fimilar to that effected on iron from the refinery by the forge hammer. It is made of a more firm texture, and drawn into convenient forms for use.

• German fteel is made by breaking the bars of bliftered fteel into fmall pieces, and then putting a number of them into a furnace; after which they are welded together and drawn to about eighteen inches long; then doubled and welded again, and finally drawn to the fize and fhape required for ufe. This is alfo called shear steel, and is fuperior in quality to the common tilted fteel.

Caft fteel is also made from the common blistered fteel. The bars are broken and put into large crucibles with a flux. The crucible is then clofed up with a lid of the fame ware, and placed in a wind furnace. By the introduction of a greater or fmaller quantity of flux, the inetal is made harder or fofter. When the fufion is complete, the metal is caft into ingots, and then called ingot fteel; and that which afterwards undergoes the operation of tilting, is called tilted caft-fteel.'

Many good obfervations on the nature of fteel, and on the mode of tempering it, are given in the clofe of the paper.

Art. 9. Remarks on Dr. Priestley's Experiments and Obfervations relating to the Analysis of atmospherical Air, and his Confiderations on the Doctrine of Phlogifton, and the Decompofition of Water. By Theophilus Lewis Rupp.-We have in this paper an able defence of the new chemical theory, against the attacks of Dr. Priestley. To feveral of the objections that have been made by the doctor we meet with fatisfactory anfwers, and to others the author has oppofed the refults of his own trials, which feem to have turned out, in fome inftances, materially different from thofe of the doctor's.

Speaking of the doctrine of phlogifton, Mr. R. obferves, P. 143, that, It is furprifing into what abfurdities and contradictions this erroneous theory milleads its ablek advocates. They fet out by declaring, that a metal

2

metal is a compound fubftance, confifting of a calx and phlogiston; that a metal becomes a calx by lofing its phlogiston *; and that a calx is reduced by acquiring phlogifton. They afterwards tell us, that a metal may become a calx, and at the fame time retain its phlogiston; and that a calx, in becoming a metal, may part with phlogiston t; and when a metal, in becoming a calx, is allowed to have lott phlogifton, they contend, that that phlogiston was not neceffary to the conftitution of the metal, provided the calx can be revived by mere heat; and, finally, that a metal has the fame properties whether it have a defici ency or an excefs of phlogiston!'

Art. 10. An Account of three different Kinds of Timber Trees, which are likely to prove a great Acquifition to this Kingdom, both in Point of Profit and as Trees for Ornament and Shade. By Charles White, Efq. F. R. s.—The kinds of trees recommended in this paper are, the black american birch with broad leaves, the athenian poplar, and the iron oak with prickly cups. This laft Mr. W. fpeaks of as growing rapidly. The other two are highly ornamental as well as good timber trees. The athenian poplar has indeed been recommended by others.

Art. 11. An Analyfis of the Waters of two Mineral Springs at Lemington Priors, near Warwick; including Experiments tending to elucidate the Origin of the Muriatic Acid. By William Lambe, M. A. late Fellow of St. John's College, Cambridge.-This paper contains a very interefting analysis of the mineral waters in the neighbourhood of Warwick, and feveral ingenious conjectures refpecting the fubftances which have been detected in them. We can only, however, prefent our readers with a hint of the author's on the medicinal properties of manganefe.

P. 210.- What,' fays he, it will be asked, are the medical properties of manganefe? Is it ufeful? Is it innocent? Is it noxious? That it is innoxious, I certainly know. Dr. John Johnstone (Effay on Mineral Poifons, p. 134.) has fhewn that it may be taken in large dofes without injury; and he has informed me, that he has fince confirmed the fame fact frequently. I wish I could as well anfwer the first queftion; but what the medical virtues of this fubftance may be, is á fubject which ftill remains in a great measure unexplored. It is certainly well worth the attention of men of fcience. To thofe who are inclined to labour in this field I take leave to fuggeft, that they should ufe either the carbonat or fome other falt of manganefe: the black oxyd, I apprehend, must be hardly foluble in the human fluids.'

Art. 12. Some Account of the Perfian Coiton Tree. By Matthews Guthrie, M D. F. R. S., &c. Communicated by Dr. Percival.-Dr. G. begins his paper by defcribing the different fpecies of the coton tree. Some doubts are then fuggefted of the fpecies of cotton here defcribed being a native of America, and on these grounds.

"Precipitate per fe (fays Dr. Priestley) is much more easily procured in dephlogifticated than in common air, and probably not at all in phlogisticated air; this air not being capable of taking any phlogiston from mercury, without which the calx cannot be formed." Experiments on Air, vol. ii, p. 185.

The azotic gas, which is mixed with the oxygenous gas, obtained from precipitate per fe, is afcribed by Dr. Priestley to phlogiston retained by the calx, with which it parts when it becomes a metal.'

P. 216. All vegetables of this genus are fuppofed to have been in digenous in Perfia exclufively; and that even the Eaft Indies derived the cotton plants from thence: a conjecture which feems to have acquired fome degree of credit from the late difcovery of fir William Jones: viz. that the hindoos, or inhabitants of India, were originally a colony of the ancient Iran or Perfia, which seems to have been the cradle of the homan fpecies, fince its ancient language appears to have been the mother of all thofe now exifting (with the exception of the arabic and tartarian), of which, nevertheless, it contained many words.

Now, it is very poffible, that the firft coloy carried the cotton plant with them to India; and that it was afterwards difperfed from Hindoftan to the adjacent countries and iflands. The cotton plant is widely difperfed likewife throughout Europe and fome parts of Africa; particularly the annual or herbaceous fpecies (the very plant treated of here) rear d in the north of Perfia, and which is alfo cultivated in Malta, Sicily, Chio, Lemnos, and other inlands of the Archipelago, although poffibly the cotton of thefe iflands may be varieties of the fpecies, from difference of foil, climate, &c.'

The cultivation of this plant is particularly defcribed, after which the author fpeaks of a fort cultivated in Germany, which he thinks may merit the attention of Portugal for their plantations in America.

F. 219. It is,' fays he, the afclepias fyriaca of Linnæus, and affords fo fine a fpecies of cotton (if I may fo name it) that fabrics have been erected in Saxony where stuffs are made of it, which rival in luftre, &c. the true animal filk. But this new vegetable filk has circumftances attending it that feem to recommend its cultivation in fome of the American colonies and islands. First, because it is originally the native of a hot climate, as Linnæus's fpecific name indicates; and, of course, it is likely to be in its greatest beauty and excellence in climates which approach nearest to that of its native country. Secondly, because its ftalks afford a coarfe fort of cloth well calculated to clothe negroes, whilft from the pith of them paper is made.'

Art. 13. Experiments and Obfervations on the Preparation, and fome remarkable Properties of the oxygenated Muriat of Potash. By Mr. Thomas Hoyle, Junior.-This is a fubitance of fuch active properties, that every fact refpecting it must be interefting to the chemiit and phyfician. On the preparation of this falt, and it's folution in water and the acids, feveral curious facts are flated. Mr. H. has found, that expofing this falt to the light in a vial does not leffen it's detonating power, which is contrary to what Chaptal has afferted.

From various experiments on the detonating and inflammable properties of this falt with different combuftible fubftances, the author finds, P. 239, that the oxygenated muriat of potah is equally harmlefs as common nitre; except it be brought into an intimate union with fomething that has a greater affinity with one of its constituent parts, than exifts between thofe parts when combined in the falt, and that fome combustible fubftance be prefent: but its oxygen being fo eafily difengaged, renders a little caution neceffary; and, as the fulphuric or nitrous acids feem fo readily to inflame many of the mixtures, I would not ad

There is a kind of cotton cultivated in Malta, of a nankeen colour, which exceeds in fineness all other cotton, and is much fuperior even to that from the Antilles.'