Imatges de pàgina
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posts in front of his intrenched camp, were made ; and bis inactivity can only be attributed to the success of this feint, which at first completely deceiveit him as to the real design; and it was not until towards the evening, when 5 or 600 men were got over, that he made any attempt to molest the enterprize. He then brought down some bartalions; but a discharge of rochets from the infantry already lodged on the right bank, threw the enemy's troops into disorder, and they soon retired.

* The ressels could not get over the bar until the evening of the same day; when by the able management and determination of the navy, but with the loss of several boats and vessels, a sufficient number to make a bridge were brought in, and it was completed on the second day following. In the meantime all the troops were crossed in boats-and the horses of the cavalry were swum over at their sterns, or transported upon a flying bridge made of pontoons.'-pp. 122, 123.

The author proceeds to treat of the passage of rivers by means of flat batteaux and portable row-boats, which is illustrated by the fatal passage of the Limat by the French, in 1799, which first gave a turn to the campaigns hitherto so favourably maintained by the Russians, as the Russian general Korzakow was in consequence driven from Zurich, and the right of Suwarrow's army completely turned, just when that general was on the point of prosecuting his Italian victories by carrying the war across the Alps.

The fourth section is occupied by an account of Aying bridges, that is, such as consist of a raft, boat, or other floating body, so suspended in the current of a river as to receive the action of the stream obliquely, and be thus forced from the one side to the other. As this species of transportation is particularly useful in desultory and daring enterprizes, it leads to a series of excellent remarks on the attempt to force the passage of rivers by open and unmasked force, which the author, after presenting us with a variety of instances from history, assures us has hardly ever succeeded when the powerful means of opposition which the river and its banks afford to the enemy have been actively and boldly employed to defeat the attempt. We extract the plan which he recommends to the defenders, as more intelligible and interesting than his mathematical and mechanical demonstrations; having great sympathy with that class of gentle readers who, far from being able to preserve their equilibrium on Sir Howard's military bridges, experience, perhaps, some difficulty in passing the pons asinorum. .

· The first consideration in defending the passage of a river, is, to take every possible measure to procure intelligence of the enemy's movemenis. Light row-boats, concealed on shore near the banks of the river, in the day time, should be used during the night, to row guard-10 descend quietly with the current, close to the enemy's bankin glide near to such places as are favourable for collecting boats; and communicate any appearance of movement. Should a surprize be in contemplation, the preparations may generally be discovered by a proper degree of bold vigilance, or at least an actual movement of boats seen, and its direction ascertained, which should instantly be communicated by signal. The different divisions of the army should be held ready to move with the greatest rapidity, and their disposition such, as to be able to oppose the first attempts to land, with a powerful force, and use the most vigorous, devoted exertions to prevent a lodgment from being made ; for, if that be once firmly obtained, we are authorized from a review of such events, in stating, that the measures the assailants will have taken to support their advance, will reinforce it more rapidly, than the defendants can possibly support theirs ; for, all the force and means of the former may have been withdrawn during the night, from points whence serious demonstrations were made the preceding evening, and opposite to which the defendants must keep in strength till the movement is unmasked.'-pp. 119, 120.

communicate gency,

The adventurous attempt to achieve a passage by udisguised force has, notwithstanding the bazard, been attempted by the best generals, remembering perhaps the maxim, in rebus bellicis maxime dominatur fortuna ;' and taking the chance of the terror and confusion of spirit which a desperate effort often strikes into a less skilful general, or troops of an inferior character. But of such enterprizes, even when successful, Sir Howard Douglas seems to speak as instances rather of fortunate audacity, than of warlike skill; and recomniends that the passage of no considerable river should be attempted without some feint or stratagem, by false attack or demonstration, to diminish the chance of resistance, and to prevent the enemy froni concentrating his forces at the real point where the passage is meditated.

In the fifth section is stated the mode of constructing bridges of various kinds, where it has been found impracticable to transport pontoons or batteaus, or to find boats. In such cases, the engi. neer lays his bridge upon rafts of timber, or upon empty casks, or upon cases rendered air-tight, or even upon inflated skins. In the last case, Sir Howard observes, with a composure which may disturb a pequin, that' the buoys should be small and numerous, to multiply the chances against injury by shot-lioles, for a single musket-ball penetrating a buoy instantly deprives it of its principle of buoyancy. To this section tables are added, containing the solid contents of timber of various lengths and mean girth ; so that upon reference to the specific gravity of the timber used to construct a raft, the quantity required to support a given weight may readily be determined. In like manner the weight of water displaced by casks of various sizes is also given, and thus the work affords every facility to the engineer, who, on a pressing emer

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gency, is required to estimate with correctness the means required for given purposes.

The sixth section treats of temporary bridges, formed by employing the carriages of an army, or composed of ropes; with directions for constructing both, and practical observations on their advantage and inconvenience. The reader might now think the engineer's invention was completely exhausted—but another section contains instructions for constructing bridges by means of tressels, of piles, of trusses, and other mechanical devices: so that the mind of the military pupil is completely stored with ingenious resources, by which in time of need and under various contingencies, he may form means of passage out of almost any thing that falls in his way.-This section, which, like the others, is illustrated by historical sketches drawn from ancient as well as modern history, is not the least interesting or likely to be the least useful. The direct information which it contains, and the hints and openings which it gives for the exercise of mechanical invention in the student himself, are equally important;-and it is scarcely necessary to add that operations carried on by such extraordinary resources of genius, are frequently successful, because an enemy often rests an undue and confident security upon the deficiency of the usual means.

The various resources by which Sir Howard Douglas 'with art pontifical proposes to turn to the purpose of the military engineer implements constructed for very different ends, remind us of an anecdote of the greatest general of the age, which used sometimes to afford amusement to those around his person. At entering a large town in Spain, it was not unusual for him to inquire particularly about the height of the cathedral or finest church of the place. These questions, which were of course considered as marks of interest taken by El Lord in their splendid ecclesiastical structures, were answered with great complacency by the authorities civil and religious. Then if it is so high, you must have long ladders for cleaning it occasionally?' This question,

This question, though its scope could not be so easily comprehended, was also answered usually in the affirmative. In which case the ladders marched on with the English waggons to assist at the next storm.

Such are the contents of this valuable manual for the young engineer. The style is plain and manly, as it should be, without any affectation of misplaced ornament; and the military illustrations are those of a soldier who has himself witnessed much in his own profession, without neglecting to avail himself of the experience of others. Some inaccuracies of the press and of the pen should be corrected in a subsequent edition ---as, p. 16, theory for theorem ;

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p. 32, weight for depth-and a few others of a similar kind, which, though trifling in themselves, are unbecoming in a book of science.

Upon the whole, the gallant Colonel has, with great credit to his own skill and accuracy,

read us matter deep and dangerous,
As full of peril and adventurous spirit
As to o'erwalk a current roaring loud,
On the unsteadfast footing of a spear.'

Art. VIII.- A Memoir on the Geogruphy of the North-Eastern

part of Asia, and on the Question whether Asia and America! are contiguous, or are separated by the Sea. By Captain James

Burney, F.R.S. From the Philosophical Transactions, 1818. SCEPTICISM

in matters of religion is generally productive of bad consequences—in those of science it is just the contrary; by provoking inquiry it frequently leads to the detection of error, and always stimulates to the discovery of truth—for in science, as in jealousy, ' to be once in doubt, is once to be resolved. In the view of the subject we are glad that Captain Burney has printed his doubts and conjectures ; and we seize with pleasure the early opportunity which his · Memoir' affords us of discussing two points of the last importance to the northern expeditions now pending,-namely, the existence of a circumvolving current from the Pacific to the Atlantic—and, of a north polar basin.

The situation which Captain Bumey held of lieutenant in the Discovery, when Captain Cook attempted to pass Behring's Strait into the arctic sea, his reputation as a compiler of ancient and scarce voyages into the South Seas, and his extensive reading and deep research in matters of this kind, are calculated to give his opinions a more than ordinary weight, and to entitle them to the fullest respect and consideration. Captain Burney is, besides, in general so orthodox, that we are unwilling to let his present heresy pass without notice, and, as we flatter ourselves, without refutation; more especially as, if his conjectures are well founded, all the past and present expeditions for the discovery of a northern passage into the Pacific will have been employed, not only on a hazardous, but on an impossible enterprize. It may be right to premise, that the appearance of this “ Memoir' in the Philosophical Transactions affords po sanction whatever for the opinions contained in it; as the Committee of Papers' distinctly state in an • Advertisement prefixed to each part of those Transactions, that • it is an established rule of the Society, never to give their opinion, as a body, upon any subject, either of nature or art, that eomes before them ;' and further, that they pretend not to answer

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for the certainty of the facts, or propriety of the reasonings, contained in the several papers published (by them), which must rest on the credit or judgment of their respective authors.'

The opening paragraph of Captain Burney’s ‘Memoir' contains the whole of the question on which we are at issue with biin.

* A belief has prevailed for nearly a century, that the separation of America and Asia has been demonstrated by an actual navigation performed; and it is distinctly so admitted in the charts. It is proposed 10 shew in this Memoir, in the first place, that there does not exist satisfactory proof of such a separation; and secondly, that from peculiarities which have been observed, there is cause to suppose the fact to be otherwise; that is to say, that Asia and America are contiguous, and parts of one and the same continent. This is not an opinion newly formed, but one which many years ago was impressed on other persons as well as on myself, by circumstance's witnessed when in the sea to the north of Beliring's Strait, with Captain Cook, in his last voyage.'-p.1.

With regard to the doubt expressed of Deschnew's voyage by sea round the north-east point of Asia, the first observation that occurs to us is the internal evidence, which the Memoir affords, of Captain Burney having confined his researches, respecting Deschnew, to the English translation of Muller's account of Russian discoveries; in ubich, as we are informed by Coxe, that of the voyage in question is extremely erroneous in some material passages. In the passage quoted by Captain Burney, however, it is neither erroneous nor obscure;-and, we should have thought, not easily capable of misconstruction. It runs thus: Deschnew, in relating his adventures, speaks only incidentally of what happened to him by sea. We find no event mentioned till he had reached the great cape of the Tschutski. Bis relation begins at this cape. It lies between the north and north-east, and turns circular towards the river Anadir. Opposite to the cape are two islands, on which were seen men through whose lips were run pieces of the teeth of the sea-lorse. Witli a favourable wind one might sail from here to the Anadir in three days and three nights. Captain Burney could not pretend that the cape or promontory here described is any other than that to which Cook gave the name of Cape East, in Behring's Strait; but he seems to insinuate that, as this was not the first cape to be doubled in going from the Kovyma (Kolyma, he calls it, following Muller) to the Anadir, the passage had been inade by land. Indeed Muller says, still quoting Deschnew's account, this was not the first promontory that occurred to which they had given the name of Swiatoi Noss;'-on which Captain Burney observes, 'the word Swiatoi signifies sacred, and is a name suitable to a promontory which could not be doubled.' But Cose tells us that Swati-noss is applied to any cape by the Russians

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