ON THE ESTABLISHMENT OF CAMPS OF INSTRUCTION IN THE BRITISH

ARMY.

for nerly forests (and are still called so); ad nirably calculated for the position of camps of this description, with every variety of ground which could be desired, equally

It is much to be regretted that circumstances have not hitherto permitted the annual formation of camps of instruction for the army in England. Their practical utility is so obvious, as to render unnecessary any lengthened discussion on the merits of a system which has proved so beneficial to the armies of the Continent. It is sufficient to observe, that they furnish the only, though a feeble substitute for the experience of actual war, without which all the theories that have ever been invented will go for very little in forming efficient officers, excepting of course, in the scientific departments of the engineers and artillery. It is in such camps, they who have already seen war, find opportunities of improving or confirming ideas suggested by former experience, and where the novice lays the foundation of a knowledge, which, whenever he is called into active service, enables him with greater rapidity to become master of his profession.

That we are not attributing greater importance to the system than it deserves, no man who knows any thing of the real duties of officers in the field can doubt. It is in this manner alone that general officers, who have arrived at that rank during a long peace, can aequire a facility in wielding and developing large masses. Here too the system of fieldfortification, the knowledge of which, to a certain extent, is necessary to all officers, and the details of outpost duties, with the precautions requisite according to the nature of the ground, may be learned more effectually than by consuming a much longer time in studying treatises on those subjects. In short, it is thus that officers of every degree, and of all arms, may become familiar with most of the operations of real war. A regiment may be perfect in all the prescribed manœuvres, when taken by itself; but in general if the commanding officer has not been habituated to act with other bodies, and to join in combined movements, he will find himself sadly at a loss, and according to the vulgar saying, very much like a fish out of water, when called upon to perform a part of them; an unlucky predicament, which, however unpleasant to himself, would not be of much importance, if it did not, as it certainly would, in real war, compromise the success of the best devised plans. We have expressed regret that circumstances have hitherto stood opposed to the formation of such camps in England. We are not, however, by any means convinced that these are altogether insurmountable. Within two or three days' easy march of the metropolis, in the northern parts of Sussex, there are tracts, which were

The situation to which we allude, has moreover great advantages from its central position, with regard to the assembling of troops. Within five days' march (exclusive of London, Woolwich, and Windsor), there are in permanent stations to the amount, on an average, of five thousand infantry, and seven hundred cavalry-the infantry consisting, it is true, principally of depôts, but still perfectly disposable in any formation. Of these, four thousand might be made at once available for the occasion, with the seven hundred cavalry. There might also, perhaps, be drawn from London and Windsor for this temporary purpose, about eighteen hundred infantry and a thousand cavalry; and another regiment of cavalry might be brought up in six or eight marches from the northeastern district; making, within a fraction, six thousand infantry, and two thousand cavalry, besides artillery from Woolwich, and sappers and miners. This force may be considered as too small to answer the purpose; but surely it is better than doing nothing: and the expense could not be much greater than in keeping these troops in quarters.

Even without forming regular camps of instruction to include the whole range of duties required in the field, still reviews upon a large scale are acknowledged to be highly useful.

Among the greatest advantages attendant' on the occupation of France by our army, together with the allies, was that of being practised each year in manœuvres on a large scale. The last, and perhaps, the most remarkable of those reviews, which took place about the end of October, 1818, was rendered additionally interesting by the circumstance, that, both at its commencement and its termination, it was held on ground illustrated by former events highly honourable to the British arms. The spot chosen for the assembly of the troops, was near the village of Villers-en-Couchie, where, four-and-twenty years before, a British regiment of dragoons (the Fifteenth, which was now present) had, by a most gallant charge, rescued the Emperor of Germany from a situation of imminent danger; and the manœuvres ended on the heights of Famars, near Valenciennes. It was also fortunate that the weather, which the preceding year had been very unfavourable, was, on this occasion, particularly fine. During the few previous days, such of the Russian, British, Hanoverian, Saxon, and Danish contingents, as were quartered at any distance, had been collected in camps and cantonments in the immediate neighbourhood; and on the morning of the re-. view the whole moved before daylight, by their several routes, to the appointed ground.

After day broke, a thick fog still prevailed for some time, and the columns, as they converged towards the place of assembly, became first aware of their contiguity to each other, by the sounds of the different national music, or the songs of the Germans

"All, as they marched, in rugged tongue, Songs of Teutonic feuds they sung;" and when the sun began at intervals to break through the fog, the glittering of arms in every direction discovered the gathering of sixty thousand warriors from so many nations. Perhaps, this was the most interesting part of the whole spectacle. The splendour of the scene, and the soul-stirring associations which came rushing on the mind, produced an effect, such as it is impossible to describe or ever to forget.

After the Emperor of Russia and the other great personages had gone down the front of the line, the manoeuvres commenced. The operations were intended to form a represent ation of attack and defence. When these were concluded, the whole army reassembled, and marched past the emperor. The marching past certainly afforded the best oppor

tunity of observing the troops of the different nations in close contrast. As regards the infantry, it may be said without boast, that the British were acknowledged to move the best. The Grand-Duke Constantine was heard to exclaim" les Gardes marchent comme des Dieux!" It was said that Constantine had, during the day, placed himself in front of the British cavalry in a charge, in order to judge of their speed, but was soon glad to fall back through an interval, finding it impossible to keep a-head of them. The strongest contrast was observed between the Russian cavalry, remarkable for the perfect uniformity and extreme simplicity of their appointments, and the variety and gorgeous appearance of the British, composed of heavy and light dragoons, Lancers, and Hussars, all of whose horses, uniforms and equipments, were most magnificent. The Saxon and Hanoverian Hussars were much admired; and the Danish light cavalry had many respectable points. As to the artillery, there is none in Europe, which can be put in comparison for a moment with the British, though few are more pleasing to the eye than the Russian drawn by their little punchy Ukranian horses. Dusk came on before all the army had passed, and thus closed a meeting of nations, which seven years before would have been considered as totally beyond the range of human events.

FRIENDSHIP.

THO' the fair field of life be o'ershadowed with sorrows,

And the groans of calamity burst on our ears;

BIOGRAPHICAL NOTICE OF

ALEXANDER VOLTA.

(Translated from the Italian.)

BEFORE the great discovery which bears his name, and which has immortalized him, Volta had devoted himself to Electricity and Chemistry. The researches of Muschenbroeck, greatly interested him, and it was not long after this, that his memoir on the attractive force of the electric fluid appeared. At a later period, he applied himself to perfecting the philosophical instruments for measuring electricity, and to the invention of new ones; the electroscopes of Cavallo, and of De Saussure, obtained in his hands the the electrophorus, and greatest exactness; the condenser, owed their origin to him. the true principles of electricity, of which it This last apparatus, especially founded on, is the consequence, is to that science, what the microscope is to natural history, in perelectricity, which, by their feeble effects, would mitting us to appreciate the quantities of have entirely escaped the means formerly known.

period, the important part, which the electric The condenser was to show, at a later agent held in nature, and the great number of phenomena which produce it, and finally it was to become, to Volta himself, the basis of his grand discovery, the means of showing that there is a development of electricity on

the contact of two metals.

It was in electricity that Volta found an explanation of the greater number of meteorological phenomena.

His hypothesis of the formation of hail, is ingenious, and his observations upon the periodical return of clouds, are not without interest; but in general, we must distinguish author, from the numerous and curious facts, throughout this subject, the theories of the with which he has enriched the science of meteorology, still so imperfect.

the labours of Volta, relative to chemistry; Let us turn our attention, for a moment to labours, which are worthy of our attention,

from their results, and from the progress of invention which distinguished them. It was he who discovered the inflammable gas of marshes, and who furnished an explanation, the consequence of the former, of the wander. ing fires, and of those igneous phenomena, which are sometimes produced upon the surface of the ground. He has shown that they result from the combustion of this gas, by means of electricity.

It was on the occasion of the discovery of an inflammable spring, which was observed to issue from a fountain in 1776, that he sus

borrows,

A balm for its pangs, a relief for its tears.

of some other similar ones, and which he at

VOL. I.

3 P

tributed, not to a circumstance purely local, but to the formation of a gas by the ferment ation of vegetable and animal substances in contact with water.

Thus he showed that wherever there was muddy ground or stagnant water, on stirring the bottom, bubbles of this gas would arise; which gas was proto-carburetted hydrogen. He explained in the same manner the cause of the burning soils of Barigazin, of the burning fountain of Dauphiny, of the igneous phenomena of Petramala, of Villeja, &c.; the inspection of places every where proved the correctness of his explanation, which had besides the positive merit of pointing out the imperfectly known cause of these wandering fires, and the advantage of showing that this phenomenon was not owing, as was supposed, to the presence of petroleum or bitumen, in the places where it was manifested.

Volta was led by the observations to which we have just alluded, to the discovery of the electrical pistol, in which, by means of an electric spark, the sudden combustion of hydrogen, produces a loud explosion. It is this property of electricity, of setting fire to inflammable gases, which, combined with another discovery of Volta, that of the electrophorus, gave birth to the hydrogen gas lamp. It is also to the same property, that we are indebted for the most exact mode of analyzing gases, particularly the eudiometer, invented by Volta himself. This instrument, the use of which is to show the proportion of oxygen contained in a certain quantity of atmospheric air, depends on different principles, all of which proceed from chemical affinities. The mode proposed by Volta, and which has been acknowledged by Humboldt and Gay Lussac, to be preferable to all others, consists in mingling with the given quantity of atmospheric air, a quantity of hydrogen more than double the quantity of oxygen, which is known to exist in the purest air, to determine afterwards, by an electric spark, the combination of the two gases, and consequently the formation of water, and to take one-third of the total diminution of the mixture, which is found to be the expression of the given quantity of oxygen sought.

It remains for us to speak of that discovery of Volta, which has contributed most to his fame, viz. the new method of producing electricity, which is called by his name, and which will always remain a monument of the genius of this learned man, to whom it owes its origin.

Galvani, being engaged in some anatomical experiments, perceived that two heterogeneous metals, connected by the intervention of a frog, suitably prepared, produced in the muscles of this animal, a sudden commotion, similar to an electric shock. This learned gentleman and some other philosophers, struck with this phenomenon, endeavoured to explain it by a fluid sui generis, which

they called animal electricity, and which they supposed to be put in action in the experiment just named. Volta's opinion was widely different from that of the authors of this hy pothesis. He advanced the idea, that this fluid was nothing more than common electricity developed by the contact of two metals, and that the frog only acted the part of a conductor and electroscope. This simple and natural explanation met with many objections. Galvani and the other philosophers alleged that it was not necessary to make use of two different metals, and that the contact of two similar metals, or even that of the muscles and nerves of the frog, was sufficient to produce the shock, which, it is true was much weaker. Volta replied that these results proceeded from this, that the metals were not perfectly the same, and that the nerves and muscles might also, as heterogeneous substances, produce electricity by their contact. Volta must be admired for the indefatigable perseverance with which he endeavoured to prove the truth of his explanation, and of the general principle, that two heterogeneous bodies in contact are in two different electrical states; he was not discouraged either by difficulty of execution, or by the ceascless attacks which were directed against him by philosophers rendered jealous by not having been able to discover a truth which was directly before their eyes. He succeeded in producing electricity simply by the contact of two metals, without the aid of a frog; he showed by means of his condenser, that the agent produced in this manner, possessed all the properties of common electricity; he replied victoriously to his adversaries, who dared no longer to oppose him, in making to the scientific world the invaluable gift of the apparatus known by the name of the voltaic pile.

Volta was led to the construction of his pile by the distinction which he established, between electro-motive bodies, such as the metals, and bodies, which are not electromotive, or only in a very low degree, but which serve only as conductors, such as fluids.

Having discovered that the contact of two different metals, called a pair or a voltaic element, produces a certain quantity of electricity, he was enabled to increase this quantity by the union of several of these elements to one another, by means of one of those conductors, such as water holding in solution a salt or an acid.

It is the union of all these couples, which is called the voltaic pile, and which forms an apparatus capable of producing electricity with a force to which no one has been able to find a limit, since there is none in the size and number of the elements which can be thus brought together.

tributes the electricity produced solely to the Volta's theory of the pile, in which he at

contact; regarding liquids as acting no other part than conductors, has been strongly attacked, particularly by the English chemists. We will not say with the author of the notice, that it may be rigorously demonstrated that the oxidation occasioned by the liquid, is only the effect, and not the cause of the electrical agent; we believe on the contrary, that if it is true, as Volta has proved it, that the contact of the metals is necessary for the production of this electricity, it is not less true also, that the chemical action of the acids, or of the saline solutions upon the metallic plates contributes much to the effect. But we must also admit that the theory of the pile is far from being perfect, and that we cannot hope to have a more satisfactory one until the numerous and various effects of this admirable instrument are better understood.

Volta has shown, as we have said before, that the agent produced by the contact of two different bodies, possesses all the properties of electricity, he showed also, that this agent accumulated in a much greater quantity at the two poles or extremities of the pile, may produce all the effects of the electricity of machines, such as attraction and repulsion, charging a Leyden bottle, &c.; and in a word, it is known that the accumulation at one of the poles is called negative, from negative or resinous electricity, and at the other pole, it is called positive, from positive or vitreous electricity.

The discovery of the pile is important, not only because it offers to us a new class of phenomena, and because it furnishes a new mode of producing electricity ;-it is especially important because it presents electricity to us under a form until then unknown, and which renders this agent capable of producing effects, some of which could not before be obtained by the aid of common machines, and others were not so strong and were always instantaneous, or not continual. We allude to the phenomena which the pile presents, in uniting the two poles by a conductor, and permitting the two accumulated electricities to reunite, and form a current, which is found to be continual, on account of the faculty which the apparatus possesses, of producing the electrical agent as fast as it is expended.

It may seem to he a departure from the subject of this article to describe these phenomena, but we think with the Italian author, that to become duly sensible of the value of the great discovery of Volta, it will be necessary to present some of the consequences which flow from it, and to show how fruitful n important results it has been in the hands of philosophers. It is not an exposition, nor even a complete enumeration of the effects of the pile that we pretend here to make; it is only some of the more conspicuous facts

which owe their origin to this apparatus, which we wish to dwell upon.

In following the author of the biographical notice, we shall recal the curious experiments of Erman, on the property which certain bodies possess, of conducting only one or the other of the electricities of the pile, and the distinction which it draws between unipolar and bipolar conductors; the different forms given to the voltaic apparatus by Volta himself, by Wollaston, Pepys, Children, Accum, &c.; the dry piles made by De Luc and Zamboni; the wet piles constructed by Davy with other substances besides metals, &c. All these details belong more properly to the theory than to the effects of the pile; as we shall partly complete them by citing with the author, the labours of Marianini relative to the electromotive faculty of certain substances, and to the influence of temperature and other circumstances, cither upon this faculty or upon conductibility; and lastly in adverting to the researches of Prof. A. De La Rive upon the electric currents disseminated in fluids, and the experiments in which he has laid hold of several remarkable analogies between electricity in this state, and the properties of light and of radiant caloric.

The services which the discovery of the pile has rendered to philosophy, are neither less important, nor less rich in consequences than those which it has rendered to chemistry. Not only has voltaic electricity furnished a new and much more powerful mode of producing heat and light, than the ancient, but it has given birth to a new class of phenomena, of a kind, then quite unknown to science.

Philosophers remarked not long after Volta had put the pile into their hands, that conductors placed between the poles would be very strongly heated, particularly metallic wire, and even platina wire would melt and burn. The most conspicuous characteristic of this kind of ignition, independent of its intensity, is, that it is continual, and has no resemblance to combustion, since it acts in a vacuum, or in gases which are not supporters of combustion, such as azote, and carbonic acid, as well as in air. In vain have philosophers every where sought to study these effects in varying and reproducing them under a thousand forms; as yet, no satisfactory explanation has been given. They have only increased the number of experiments, and here we ought not to forget to mention that of Davy, one of the most remarkable in experimental philosophy; we mean the brilliant jet of light that this able chemist has produced between two pieces of carbon, in connecting them with each pole of the pile.

Ever since the earliest inquiries into the nature of electricity and magnetism, philosophers have suspected that an analogy ex

isted between these two agents, but this, until 1820, had been purely hypothetical.

It was reserved for the voltaic apparatus to show by facts the truth of this analogy; it is to Oersted that we are indebted for having known how to prove this experimentally; he discovered the action which a conductor, uniting the two poles of the pile, exercises upon a magnetic needle.

If we have thus far adopted the order of ideas traced by the Italian author, without however subjecting ourselves to the necessity of following him step by step, and omiting nothing which he has said, or adding nothing to his exposition, we are now obliged to abandon him entirely. In fact, after having claimed the honour of the experiment of Oersted in favour of two of his fellow citizens, Mojon and Romagnesi, be satisfies himself with recalling the determination by Biot and Savart, of the law which governs the new action, and the very remarkable fact discovered by M. Arago, of the magnetism given to needles of steel by an exterior electric current. But by a forgetfulness which we cannot account for, the author does not mention the name of M. Ampere, of that philosopher, who may be justly called the creator of a new branch of physics, called electro-dynamics; the history of the labours of this philosopher is the best homage that we can render to the memory of Volta, since they show of what great theoretical and experimental discoveries the pile has been the origin.

M. Ampere had for a long time meditated on this subject, and he appeared only to wait for a favourable opportunity, to give vent to the results of his meditations; when the discovery of Oersted suddenly appeared, he immediately availed himself of it, and by his labours, laid the foundation of a new science. Whatever may be the present and future opinion relative to the ingenious theory which this philosopher has sought to establish, the numerous facts by which he has enriched science, will always remain a monument of the services which he has rendered, and if some difficult minds should find his explanations insufficient, his hypothesis a little too bold, let them not forget at least, that abstractly from their intrinsic merit, it is these explanations, these suppositions which have given birth to numerous experimental discoveries.

The first step that M. Ampere made on electro-dynamics, was to discover, that, independently of the influence which the electric currents exercise upon the magnetic needle, they exert also an action upon one another, the law of which he determined. He soon went farther; instead of imputing, as all other philosophers at first did, the influence which a conductor of voltaic electricity exercises upon a magnet, to a magnetism impressed into this conductor, by the

current, he showed with much sagacity that the magnet itself is nothing more than a union of electric currents, and that the action discovered by Oersted is only a more complicated case of the simple action of two currents upon one another. As a proof of the identity which he established between magnetism and electricity, M. Ampere shows that all phenomena relative to the action of magnets and currents, even the singular movements of continual rotation discovered by Mr. Faraday, with the action of magnets upon one another may be explained, by supposing that the latter are formed by an assemblage of electric currents disposed agreeably to a certain order which he was enabled to imitate, so as to obtain a real magnet, only by means of electricity.

Lastly, he has gone still farther, in showing that an electric current possesses, like the compass needle, the property of assuming a constant direction by the action of the terrestrial globe. He has subjected this action of the globe, both upon the moveable current and upon the magnet, to that which an assemblage of electric currents would exercise when directed from east to west, towards the equator. Now every thing conspires to prove the correctness of this supposition. Davy has discovered by means of the piles, that all bodies which we call earthy, are metallic oxides; it is then probable that below the oxidized crust of our globe, there are metals in a pure state, which are continually acted upon by the surrounding agents, such as water, and we have thus an active source of electric currents, on which the earth's rotation tends to impress a determined direction.

What an admirable connexion does the explanation of M. Ampere, which we have just presented, exhibit. It is the pile which teaches us that an electric current is under the influence of the earth; it is the pile which teaches us that all the substances of which the earth is composed, are metallic oxides; these two facts, which, at first view, have no other relation to each other, than that of arising from the same source, are found, by an ingenious theory, to have an intimate application to each other.

If we were to enumerate all the services which the pile has rendered to science, we should be obliged to surpass the bounds within which this article must necessarily be limited. We regret that we cannot enlarge upon the important labours of Mr. Becquerel, upon the recent researches of Mr. Savary relative to the very remarkable phenomena which he has discovered in the magnetism of steel by electric discharges, and that we cannot dwell upon other numerous experiments made by philosophers of various countries. The foregoing account is sufficient, we think, to show what an inexhaustible mine of rich discoveries Volta has put into