Изображения страниц
PDF
EPUB

ascribes solely to the diffolution of the pure air, the principle of which unites itself with the metal; as, in these experiments, the mercury had not acquired any sensible heat. Two inches and three-quarters of the same kind of air being placed over water, and electrified in the same manner during half an hour, loft a quarter of an incb; and being suffered to stand twelve hours in the tube, was found to have lost one-eighth of an inch more. This was very nearly the same diminution of the air that had taken place, when it was electrified over mercury; but, in this case, the process appears to be more flow, and the detached principle not so readily absorbed. The air remaining after these experiments, being tried by the eudiometer, did not differ from unele&rified pure air taken from the same receiver. .

To determine whether the pure air retained any of the acid employed in its production, the Doctor repeated the experiment with air, obtained from red precipitate, confined by an infusion of turnsole, but could not perceive in it the least change of colour. He also electrified air, obtained from minium and the vitriolic acid, placed over some diluted vinegar of lead, but this was not rendered at all turbid.

Three inches of phlogisticated air being electrified, during the first five minutes, were augmented to 3 ; inches, and, in the next ten minutes, to 3 inches: some lixivium was then introduced to try' whether this would absorb it; but, upon being electrified fifteen minutes, the column rose to the height of 31 inches. It was suffered to stand in the tube till the next day, when it was found to have sunk to its original dimension.

Nitrous air, confined by lixivium, being electrified during half an hour, lost three-quarters of its bulk; the lixivium appeared to have absorbed a great deal of nitrous acid; and the air remaining in the tube did not seem to differ from common phlogisticated air. Some of the same nitrous air, confined by lixivium, was, by standing three weeks, diminished to half its bulk, and this residuum also proved to be phlogisticated air, Thus electricity very speedily effects that separation of the nitrous acid from nitrous air, which is Nowly produced by the lixivium alone.

Inflammable air, obtained from steel filings and the diluted 'vitriolic acid, being confined by an infusion of turnsole, was ele&rified for ten minutes without any change of colour in the infusion, or any alteration in the dimension of the air. The tube, being filled with the same air to the height of 2 ] inches, and placed in diluted vinegar of lead, was exposed to the electric ftream during twelve minutes, in which time the inclosed air rose to five inches; but the vinegar remained perfectly clear. Three inches of inflammable air, obtained from a mixture of Spirits of wine with oil of vitriol, on being electrified for

fifteen fifteen minutes, rose to ten inches ; thus dilated, it loft all its inflammability, and when nitrous air was added, no diminution ensued. :

A column of alkaline air, obtained by heat from Spirit of fal ammoniac, three inches high, was electrified four minutes, and rose to fix inches, but did not rise higher when eledrified ten minutes longer. It appears that this air is not expanded more by the powerful electric stream from this machine, than by the common spark. Water would not absorb this electrified ais, which was in part inflammable.

The cube, being filled, to the height of an inch, with spirit of fal ammoniac, and inverted in mercury, was electriñed four minutes; in which time, the tube was filled with eight inches of air, which proved to be equally inflammable, and as little absorbed by water, as the alkaline air. Hence Dr. VAN MARUM conjectures that this air is only the volatile alkali rendered elastic,

The last chapter contains an account of a very ingenious experiment to illustrate some phenomena observed in thunderftorms. Two balloons, made of the allantoides of a calf, were filled with inflammable air, of which each contained about two cubic feet. To each of these was suspended, by a filken thread about eight feet long, such a weight, as was just sufficient to prevent it from rising higher in the air ; they were connected, the one with the positive, the other with the negative conductor, by small wires about thirty feet in length, and being kept near twenty feet alunder, were placed as far from the machine, as the length of the wires would admit. On being ele&rified, these balloons rose up in the air as high as the wire allowed, attracted each other, and uniting, as it were, into one cloud, gently descended. The rising of these artificial clouds is ascribed to the expansion of the air they contained, in consequence of the repulsive force communicated to its particles by ele&ricity : when in contact, their opposite electrical powers destroyed each other, and they recovered their specific gravity, by losing the cause of its diminution. In order to render this experiment more perfectly imitative, the Doctor suspended to the balloon which was connected with the negative conductor, a bladder filled with a mixture of inflammable and atmoípherical air, which, being kindled by the (pask that took place on the union of these clouds, gave a considerable explosion. From these experiments, the Doctor explains the tudden elevation of the clouds, and che violent showers of rain and bail, which often accompany thunder-storms.

Dr. VAN MARUM intends to make considerable additions to . his battery, as he finds that the machine is capable of charging a larger surface of coated glais; and defigns, in his next pub

lication,

lication, to give an account of experiments on femi-metals, and of chose which have been proposed to him by orber electricians, whom he here invites to communicate any hints, that may tend to further discoveries in this important branch of phylics.

For the unusual length of this article, perhaps lome apology may be necessary; but we hope our readers will excuse it, when they are informed, that on account of the plates, and the comparatively small number of copies, this interesting work will probably soon become very scarce.

ART. XIII. The Forms of Herkern : corrected from a variety of Manuscripts,

supplied with the distinguishing Marks of Construction, and tranla lated into English, with an Index of Arabic Words, explained and arranged by their proper Roots. By Francis Balfour, M. D. 410. Ilois. Printed at Calcutta ; and fold by Richardson, London. A PERFECT knowledge of the Eastern languages is a matn ter of great importance to the merchant as well as the linguilt. The encouragement which Mr. Hastings gives to every attempt toward illuftrating the antiquity and customs of the Eastern nations, and to the study of their languages, has, in a great measure, been the means of producing the learned performance before us. It is an edition of a work held in much eftimation among the teachers of the Persian language, and which is put into the hands of every beginner, being more immediately useful to strangers, as it relates to the common forms of business and correspondence. Dr. Balfour has collated several manuscripts, in order to render the copy as perfect as posible; and this will appear to have been a work of no small labour and difficules, when it is considered that the Persian manuscripts are extremely inaccurate, the distinguishing points of letters being often superfluous or misplaced, and the letters themselves contracted and deformed, not to mention the great obfcurity that is occafioned by words being wrongly divided, or written witbout any diftinction or spaces between them, and even whole books without the division of sentences. Dr. B. having given a correct edition, where the words are properly marked and divided, has certainly presented the learners of this language, and the curious in Eastern literature, with a most valuable períormance : in order to make this work more generally useful, ihe Doctor has given an Englich translation of the original on the opposite page, and annexed a copious vocabulary, or dictionary, of Arabic words, with the derivatives under their proper roots.

Asche Insha-i herkern contains forms of oriental correspondence and bufin is, we mall present our Readers with the following hori specimen of an Eastern love-letter :

6 0 moon

· O moon of the heaven of goodness! O cypress of the garden of affection ; O light of the eye of lovers ; O joy of the affectionate heart! out of your benignity and kindness you promised to enlighten the cell of my melancholy with the ray of your exhilarating presence. Veriiy, since that time, the eye of hope is upon the high road of expecta. tion. Since the days you said, I will come, mine eye is upon the road: why do you burn me with the caustic of expectation? why don't you come? If agreeable to your promise, you should give, by a joyful sight of you, illuminating brightness to the longing eye of your friends; no wonder at the excess of your kindness.

" Come, come, for I love you with an hundred souls.

" Come, for I am torn from myself and united with thee." The Answer to the above,

• O afflicted lover and forsaken expectant! I have understood that you long to see me, and still preserve your attachment to me. But you ought not to depend on the promise of beauties ; you ought not to set your heart on their assurances.

“ Amongst beauties nobody ever met with fidelity;

Nor with any thing but schemes to torment.” Nevertheless, if the lover be fincere, and content with beholding, what objection is there?

“ When lovers are sincere in their affection,

" What harm though beauties attach themselves to them?”. Want of firmness will not do; patience is requisite. The moon of my beauty may soon fine from the window, and the tree of my fa. ture may cast its shadow on the terrace.

" Patience is bitter, but it bears sweet fruits," Among the forms of business is the following certificate of the sale of a slave girl.

• Khojeh Abdulla, son of Khojeh Mahommed, being of age, and in full possession of all his faculties, affirms and declares to this effect: “I have sold to Meer Darvailh Mahommed, son of Mahommed Morad, a slave girl named Gulbehar, of a copper complexion, and middle fize, with grey eyes, high nose, joined eye-brows, and both ears pierced, supposed about twenty years of age, for the sum of twenty current rupees, the half of which is ten, which sum I have received." These few lines were drawn out in court, by way of certificate, on the eleventh of the month Zeekkadeh.

This work is a curiosity, on account of its being the first printed book in the Taleek character. Considerable merit is due to Mr. Wilkins, without whose afliftance the Injha-i berkern could never have appeared in its present form; as is cvident from the following passage in the Preface :

The only printed Persian character that has hitherto been in use, except in exhibiting fair copies of dictionaries and grammars, has been subservient to no public purpose ; and is but ill calculated for becoming the channel of authority, or the medium of business, over an extensive empire, where it is almost unknown, and scarcely underftood; whereas the types which Mr. Wilkins has invented, being a perfect imitation of the Taleek, the character in which all Persian books are written, and consequently familiar and universally read, are not only well calculated for promulgating the edicts of govern

ment,

ment, but for every transaction in business where the Persian character is required.

* By this invention (which is perfectly new and peculiar to Mr. Wilkins, and at the same time the labour of his own hand, from the metal in its crudest state, through all the different stages of engraving and founding) the Persian language may now receive all the assistance of the Press. The most valuable books may be brought into print; the language may be more easily and perfectly acquired; and the improvements of the learned and industrious conveniently communicated to the Public, and preserved to posterity.'

We congratulate the cultivators of Eastern literature on the acquisicion of so great an assistance in facilitating the study of it; and we hope that by this means not only the languages, but the learning and philosophy of the East, will be more generally known among Europeans.

ART. XIV. De la France et des Etats-Unis, &c. i. e. On France and the United

States; or, on the Importance of the American Revolution to the Kingdom of France, and the reciprocal Advantages which will accrue from a commercial Intercourse between the two Nations. By Stephen Claviere and J. P. Brissot de Warville. 8vo. 6s. Boards.

Phillips, London. 1787. T VERY nation is benefited by commerce, and the advantages

L of a commercial intercourle between two nations, will always be proportional to the neceffities of the one, and the proa ductions of the other. The Authors of the present publication, by comparing the wants of the Americans with the productions of France, and the contrary; and by considering the relative situations and circumstances of the two countries, prove, that a well-regulated commerce must be highly beneficial to : each.

The first Chapter is employed in defining several terms, and in explaining the general principles of a foreign trade [commerce exterieur). The Authors shew that a direct trade (i.e. a trade carried on between two nations immediately) is preferable to that which is carried on by the intervention of a third; it enables the merchant to afford his goods at a cheaper rate; and the cheapness of goods is the very basis of a foreign trade. They point out the circumstances which enable a nation to sell its productions cheap, and also the circumstances which oblige two nations to enter into a commercial intercourse. They consider the mutual interest of the two nations, and the nature of things, to be the only means of establishing a fure trade. Treaties, re. gulations, laws, and force, are of no effect; all of them muft give way to the nature of things.

The authors next enter into an examination of what is meant by a balance of commerce. Here we are presented with lonie cuApp, Rev, Vol. LXXVI, SE

sious

« ПредыдущаяПродолжить »