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184 Analytical Notices.-Encyclopædia Britannica-Supplement.

paper in place of specie; country banks in Britain; system of banking in Britain; mode of settling the daily transactions of the banks in London; disadvantages incident to a currency of paper; policy to be adopted by the Bank of England in a disordered state of the circulation; dangers to which banks of circulation are exposed; interruption of credit in 1793 and 1797; suspension of cash payments by the Bank of England, and reasons for continuing that suspension; chartered banks of Scotland;* Bank of Ireland; and Bank of France.

Of the article on BANKS FOR SAVINGS we forbear to say any thing at present, as the merits of that article have already been adverted to in our former Number, and we believe the subject will soon be resumed.

In the account of the BARBARY STATES, which our limits allow us merely to mention, there is some recent and curious information, particularly with regard to the condition of Christian slaves.

To the article BAROMETER our attention must be more particularly directed. The able writer of this article, beginning with a concise and elegant summary of the opinions of the ancients concerning the system of the material world, and shewing how the mutual opposition of the academicians and peripatetics discouraged the application of mathematical reasoning in physical research, then proceeds to trace the progress of experimental science from the wild but beneficial projects of the alchemists, through the more sober and regular steps which have raised her to her present commanding elevation. In this enlightened survey, he is led to mention some of the most curious and instructive facts in the history of knowledge and of the human mind. It is well known how much, after the restoration of letters, a reverence for antiquity, and particularly for the tenets of Aristotle, repressed the ardour of philosophical adventure. It was a

There are at present in our metropolis three banks incorporated by charter; namely, the Bank of Scotland, established by act of Parliament in 1695; the Royal Bank of Scotland, established by royal charter in 1727; and the British Linen Company, originally incorporated in 1746, with a capital of £100,000, for the encouragement of the linen manufacture.

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maxim of ancient philosophy, that nature abhors a vacuum; and to this abhorrence were ascribed all the effects which result from atmospherical pressure. An incident, apparently trivial, first led to the refutation of that absurd opinion. Some artisans in the service of the Grand Duke of Tuscany, having been employed to construct a sucking pump for a very deep well, were surprised to find, that in spite of all their care in constructing the pump, they could not raise the water higher than 32 feet. For an explanation of this perplexing fact they applied to Galileo, whose ingenuity had already prepared a complete revolution in science. Galileo had, by some interesting experiments, obtained a tolerably correct notion of the weight of air; but the horror of a vacuum was an established principle, which he had not the boldness to question; and he endeavoured to explain this seeming anomaly, by supposing the influence of the horror to be confined within certain limits, not exceeding the pressure of a column of water 32 feet in height. He was dissatisfied with his own explanation; instituted an experiment which brought him almost within sight of the truth; and communicating his doubts and his conjectures to his disciple Toricelli, led him into the tract of more successful experiment.

The celebrated experiment of Toricelli, and the still more decisive experiments of Pascal, one of the finest and most original geniuses that France ever produced, at length exploded, though not without a violent struggle, the long received maxim of the abhorrence of a vacuum; and proved, with the evidence of demonstration, the pressure of the atmosphere." On the whole," says the author of a well-written article on the same subject, in the Edinburgh Encyclopædia, "the history of this research affords a signal instance of the slow and gradual progress of human knowledge. Galileo proved that the air was possessed of weight; Toricelli conjectured that this fluid caused the ascent of water in pumps, as well as the suspension of mercury in the tube, which bears his name; and Pascal converted this conjecture into a de monstration."-We have been led so

far beyond our limits, by the interesting nature of these facts, that we can barely mention the other subjects

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1817. Analytical Notices.-Encyclopædia Britannica.-Supplement.

which this article embraces. An ac-
count is given of the invention of the
air pump, by Güricke of Magdeburg,
about the middle of the seventeenth
century, of his statical balance and
anemoscope: the introduction of ex-
perimental science into England, and
the institution of the Royal Society,
are next related; this naturally leads
to the mention of some of its most ce-
lebrated members, as Boyle and Hook,
the latter of whom greatly improved
the form of the air pump; next come
the experiments of Huygens, who,
from the suspension of mercury in a
glass tube exhausted of air, was led to
infer the existence of a more subtile
fluid, which he called æther: the cis-
tern barometer is then described; after
which are detailed the various con-
trivances for enlarging the scale of the
variations of the barometer;-first in
order is the barometer of Descartes;
then the double barometer of Huy-
gens, the advantages and disadvan-
tages of which are pointed out; next,
the more accurate double barometer,
and the wheel barometer of Dr Hook;
the inclined barometer, ascribed to Sir
Samuel Moreland; the square baro-
meter of Cassini and Bernoulli; the
conical barometer of Amontons; the
sectoral barometer proposed by Ma-
gellan; the adaptation of the differen-
tial scale for measuring minute divi-
sions, first proposed by Vernier, early
in the seventeenth century, but long
afterwards strangely neglected ;-the
article next proceeds to mention the
circumstances which influence the va-
riations of the barometer, viz. the effect
of moisture within the barometric
tube,-the effect of the width of the
tube-the uniform convexity of the
surface of pure mercury in properly
constructed barometers,-the quantity
of depression in different tubes,-the
application of a leather bag to the sy-
phon barometer, the effect of heat on
the barometer, which leads to an ac-
count of the successive improvements
of the thermometer; marine barome-
ters are next described, the most ap-
proved kind of which, manufactured by
Mr Cary of London, is illustrated by a
figure, in a well executed plate-the
difficulty of explaining the variations
of the barometer are adverted to, and
some hints are thrown out relative to
these causes.
On the whole, we think
this a very able article, though, per-
haps, a little too discursive.
VOL. I.

185

As a sequel to the article BAROMETER, we have, from the same pen, a paper on BAROMETRICAL MEASURE MENTS. The decisive experiment by which Pascal ascertained that the pressure of the atmosphere diminished according to its elevation, naturally suggested to him the possibility of measuring by the barometer the relative heights of distant places on the surface of the globe. The first attempts, however, were rude, as they proceeded on the inaccurate supposition that the lower mass of air is a fluid of uniform density. We regret that our limits prevent us from accompanying Mr Leslie in tracing the successive steps by which the instruments and the rules employed in barometrical measurement have attained their present state of perfection. One interesting discovery, however, lately made by this mode of distant levelling, we must, in justice to our readers, mention. Two Prussian travellers, Engalhorde and Parrot, who proceeded, on the 13th July 1814, from the mouth of the Kuban, on the Black Sea, to the mouth of the Terek, on the Caspian, ascertained, by a series of fifty-one accurate observations, that the Caspian is 334 English feet below the level of the ocean; and that, at the distance of 189 miles from the Caspian, the country is depressed to the level of the ocean-thus leaving an immense basin, from which the waters are supposed to have retired by a subterraneous percolation.

In the article BATHING, the medical and physical effects of the various kinds of baths, in various circumstances, as determined by the observations of Wright, Currie, Seguin, Parr, Haygarth, Fourcroy, Marcard, and other able physicians, are minutely and accurately detailed.

The article BEAUTY we opened with peculiar interest; and though we are very far from agreeing to the theory proposed, and the reasoning by which that theory is supported, we are ready to do full homage to the abilities displayed in the discussion. We cannot say, however, that we greatly admire the style in which the article is composed. It is distinguished, indeed, by great vigour of conception, and by a command of language almost peculiar to its celebrated author; but the vehemence of its tone, and the dogmatical confidence of its assertions, remind us 2 A

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more of the manner of a pleader at the bar, anxious at all events to make good his cause, than of the calm and dispassionate style of a philosophical inquirer of which Mr Alison and Mr Stewart, in their treatises on the same subject, had given so pleasing specimens, We shall not at present attempt any analysis of the contents of this article, as we hope soon to have a communication on the subject from a correspondent.

Under the article BEE, the many curious and interesting facts relative to the physiology and economy of these remarkable insects, which have been discovered by the researches of Swammerdam, Maraldi, Reaumur, Schirach, and Huber, are detailed in a clear and systematic manner: but as these facts are now so generally known, we think it unnecessary to give any analysis of the article.

BEGGAR is the next subject that claims our attention. The information contained in this article is chiefly drawn from the report of a committee of the House of Commons, appointed, in 1815, to inquire into the state of mendicity in the metropolis. Beggars are classed into those who beg from necessity, and those who beg from choice. With regard to the relative numbers of these classes, the information of the committee was quite contradictory. Two of the witnesses examined, whose experience was equal or superior to that of all the rest taken together, asserted, that a proportion as large as one half were beggars from necessity, and some of them extremely worthy objects of compassion; while others asserted, that all beggars, with hardly any exception, were beggars from choice. One fact, extremely honCourable to the working part of the community, seems to be well ascertained. Of the journeymen in the metropolis, no one is ever known to beg, though thousands of them, in the fluctuations of trade, have been reduced to the most cruel privations; and not a few of them actually starve unpitied and unknown! The number of beggars in the metropolis the committee have been unable to ascertain; but it appears to be certain that it is gradually diminishing. Of the decep tions practised by beggars very erroneous notions have been entertained. In the number and variety of their contrivances they are supposed to exercise

wonderful ingenuity; whereas their expedients are few, obvious, and coarse. Of the methods proposed for suppressing begging, there seems to be none so deserving of approbation as the scheme of the society at Edinburgh for that laudable purpose. Nothing can be more judicious than the principles on which the society proceeds; and their exertions have met with the success to which they are so well entitled. It is objected to their plan, by the writer of this article, that it is not calculated for permanent or general use. their example be generally followed, and there can be little doubt that it will be found generally beneficial.

Let

The article on BENEFIT SOCIETIES proceed from the same pen, and is marked by the same prepossessions as the article on Banks for Savings. It is unnecessary, therefore, to say any thing of it at present, as another opportunity will offer of examining the doctrines and the principles which it contains.

Besides the articles to which we have already adverted, this part of the Encyclopædia contains some good biographical sketches of Joel Barlow, Barry, Barthez, Basedow, Beattie, Beaumarchais, Beccaria, Beckmann, and Beddoes.

EDINBURGH ENCYCLOPEDIA, Vol. XI. Part I.

Two different plans have been adopted by the editors of Encyclopædias, which may be distinguished by the epithets of alphabetical and scientific. In the Cyclopædia edited by Dr Rees, there is indeed a vast treasure of valuable knowledge; but the plan of that work appears to us, in several respects, essentially faulty. One grand objection to it is its extent, which places it far out of the reach of ordinary readers; another objection, the consequence, indeed, of the former, is the enormous length of most of the articles, which, instead of being compendious treatises, are prolix and ill digested compilations, apparently intended to contain every thing that seems to bear, however remotely, on the subject; but a still more important objection is the want of unity, occasioned by dividing a subject into separate departments, which are discussed in different, and often distant, parts of the work. The Edinburgh Encyclopædia, on the other

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hand, by a judicious plan of selection, reserves a due space for the discussion of important subjects, while it is overloaded with no useless and lumbersome matter. Its plan is sufficiently extensive to embrace every thing useful in history, literature, and science, but not so extensive; and herein lies its excellence, as to admit of the tedious and perplexing tautology, which is unavoidable when the same subject is brought under the view of the reader, in different articles, and in various forms. The respectable names which appear in the list of its contributors were, from the first, a pretty sure pledge of the ability with which it would be conducted; and the pledge has been fully redeemed. Many of its leading articles may be held forth as the best treatises which have appeared on their respective subjects; and the plan very properly adopted, of having every article an original communication, marked by the signature of its author, has excited among the contributors a very beneficial emulation, and conferred on the work a uniformity of excellence of which none of its rivals can boast.

Our notice of the articles which this half volume contains must be extremely brief; and this we are the less disposed to regret, as there are not many of them which can be supposed to be very generally interesting. The first in order is HERPETOLOGY, the natural history of reptiles. Under the term reptiles, it is observed, naturalists have generally comprehended all those tribes of oviparous animals commonly called amphibia, including both oviparous quadrupeds and serpents; but in this article it is proposed to consider only the first order, reserving the history of the serpent tribes for the article OPHIOLOGY. The account which is given of these animals, and of the history of the science, is methodical, clear, and comprehensive; accompanied with a full list of references, which will be found very useful to those whose attention is directed to this department of zoology. The reptile tribes are distributed into three orders, Chelonians, Saurians, and Batracians. The first order comprehends turtles, of which there are six species, and tortoises, of which there are fifty-two species. The second order comprehends crocodiles, dragon, basilisk, tupinambis, guana, flying-dragon, agamas, stellios, cha

meleons, geckos, anoles, lizards, takydrome, scinks, efts, and chalcides. The third order comprehends the hylæ or tree frogs, rana or common frog, bufo or toad; these constitute one family, called the batracians, without tails; the other family (or tailed batracians) consists of the salamander, proteus, and siren. In treating of the anatomy and physiology of these reptiles, the author gives a clear and comprehensive account of their motions, sensation, digestion, circulation and absorption, respiration and voice, secretion and excretion, integumation, generation, and hybernation.

HISTORY is the next article of importance. The plan proposed is, first, to point out and explain the various advantages of the study of history; secondly, to enumerate those branches of study which ought to be entered upon, previous to, or contemporary with, the study of history; thirdly, to give a brief and rapid sketch of the order in which ancient and modern histories may most conveniently and advantageously be read; fourthly, to point out the order in which the history of particular countries may be read, so that they may be illustrative of one another; fifthly, to notice the different species of history, besides what is emphatically called history. Notwithstanding some defects, this article may be perused with considerable advantage by those who wish_to_commence a regular course of historical reading.

The account of the province of HOLLAND is full of important and interesting information. Indeed the geographical articles of this Encyclopædia are distinguished in general by the extensive and accurate knowledge which they display, and by a happy discri mination, which rejects all extraneous matter, without omitting any thing that it is useful to know. The lan guishing state of manufactures and commerce in that once flourishing country, affords a striking exemplification of the vicissitudes of national prosperity. We have no room for de tails; but, as a proof of the declining condition of the country, we may state, that, since the year 1732, the population of this province had, even previous to 1796, decreased by one thirteenth of the whole; that, except the internal trade with Germany, its com-merce is almost annihilated; that many

of its principal manufactures have gone to decay; and that the only one which is on the increase, is the distillation of ardent spirits.

The article NEW HOLLAND Supplies the information, which the publication of Captain Flinders' discoveries has put us in possession of respecting this island, since the article Austral asia was written. The author of these articles, however, seems to have known nothing of the journeys of Mr Evans and Governor Macquarrie into the interior-a deficiency which, we doubt not, the attention of the Editor will take the earliest opportunity of supplying. In other respects the article is valuable; containing an accurate and well-digested account of the coasts and bays, the mineralogy, botany, and zoology, of this immense island; of its inhabitants, their arts, manners, and customs.

Our attention is next arrested by a very long article on HOROLOGY. We are told by the Editor, that he is indebted for this article to Mr Thomas Reid; and this may be regarded as a pretty sure pledge of its technical accuracy. On the whole, we consider it as the best account of horology that we have seen, so far as the practical part of it is concerned; and as many of the improvements on various branches of the art were invented by Mr Reid himself, no person, surely, could be better qualified to describe them. The departments of this curious art we shall inerely mention, in the order in which they occur in Mr Reid's description. 1. The escapement, or 'scapement, that part of a clock or watch connected with their beats-on this part of the machinery Mr Reid has made several improvements; connected with the escapement is the remontoir, the intention of which is, that the move ment passing through the wheels should, at intervals, be made either to wind up a small weight, or to bend up a delicate. spring, which alone should give its force to the 'scapement; by which means the pendulum or balance was supposed to be always impelled by an equal and uniform force-Mr Reid has described a remontoir which he applied to the clock of St Andrew's Church in Edinburgh; 2. the compensation-balances, intended to counteract the effects of heat and cold on time-keepers; 3. balance or pendulum springs; 4. jewellery of

pivot-holes; 5. machinery for going in time of working, invented by Harrison-a contrivance of his own for this purpose is described by Mr Reid; 6. the dividing or cutting engine; 7. equation-clocks, an ingenious contriv ance to show both mean and apparent time, invented in London about 120 years since; 8. repeating clocks and watches; 9. compensation-pendulums, two kinds of which have been invented by Mr Reid, the one with a zinc tube and steel rods, the other with a glass tube; 10. wooden pendulumrods, on which Mr Reid made some experiments, which he details; 11. on the sympathy or mutual action of the pendulums of clocks; 12. on turretclocks; 13. on the method of fitting up astronomical clocks; 14. on chimes and bells.

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To the amateurs of gardening, the article HORTICULTURE must prove an exquisite treat; while to the practical gardener it will afford much valuable instruction. It is evidently written by a person who not only understands the subject in all its practical details, but who has brought to that delightful study an elegant taste, and a philosophical mind. We cannot afford, at present, to give any analysis of so long an article, or even to mention the various topics which it comprehends. His own definition of HORTICULTURE, however, will give some idea of the principal branches into which the subject is divided. By the term horticulture," he observes, "is to be understood the whole management of a garden, whether intended for the production of fruit, of culinary vegetables, or of flowers. The formation of a garden may be included also, to a certain extent, under this subject: draining, enclosing, and the forming of screen plantations and hedges, may be considered as parts of horticulture, while the general situation of the fruit and the flower gardens, in regard to the mansion-house, and the position of some of their principal component parts, as shrubberies, hot-houses, parterres, and walks, belong more properly to landscape-gardening."

Thus we have adverted, in a very cursory manner, to the leading articles in this half-volume. It contains, besides, several excellent articles in biography, geography, &c. On the whole, we think that this number supports well the credit of its predecessors.

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