that joining the axis of the earth and moon; when in this position, raise or depress the moon on its pedestal till its centre is at the same height as the earth's above the surface of the board; that is, the moon must be put really in the ecliptic when she is in her node; and the corresponding adjustment for the sun's centre may be made at the same time. Then move the frame, H, till its axis, or the line parallel to the radius vector of the moon, point to the degree of longitude on a, in which the moon is at the time of adjustment; in this new position, turn the lower pedestal of the moon round on its axis, till that axis is perpendicular to the ecliptic; a small index stuck in the pedestal to point to the right degree on the divided circle, will allow of this adjustment being made with facility and accuracy at once*. Lastly, move the frame, H, backwards or forwards till the moon be brought to her true distance from the earth at the time of adjustment, by means of the scale on the slips; and set the enlightened half of the moon towards the sun, that is, make the plane of the line separating the light dark halves perpendicular to the sun's direction. The board may be made to slide between fillets of wood nailed down on one much larger. These fillets being struck out, arcs of concentric circles of such radii, that the path of the earth, when moving between them, may be the circle described by the earth at its true proportionate mean distance, deduced from that originally assumed for the earth and moon: these fillets may be spaced out into days: this addition to the Lunarium will enable it to show that the curve described in space by the moon, is not a nodated cycloid, as common orreries show it, but one slightly undulatory, and always concave to the sun.

The young learner must be impressed with the characteristic of this instrument, in which, indeed, its great merit consists; it is only true for one fixed position, and will not admit of the moon's being made to revolve round her whole orbit, for before she has moved through one twentieth part, her mean distance and the place of her node has altered, but by the simple and easy adjustments which a common ephemeris will enable him to make in as short time as is requisite to read these instructions, he has the earth and moon in their real positions, and by moving the moon for a short arc in her orbit, he sees the direction of her motion and its results. But if he look through the hole on K, he must bear in mind that he is no longer an observer from the earth, he must transport himself in imagination to the sun, or at least to the point in the earth's radius vector, represented by the aperture on K. He will see an eclipse of the earth when to an inhabitant of it the sun is eclipsed, and he will observe an eclipse of the moon by the body of the earth, instead of its being obscured only by passing through the shadow of our planet. By

* The degrees on that circle must be numbered accordingly, but the means of ascertaining where they are to commence will be best understood by looking at the instrument; it should be contrived that the small index should point when the adjustment is made to the degree of the circle on a, seen in the axis of H: when, therefore, the moon is in her nodes, the index on the pedestal must point to 0° or

180°, no description can make these niceties intelligible to the dull, and they are not needed by the acute: all that can be said is, that the moon's axis must be perpendicular to the ecliptic, and not to the plane of H, otherwise there will be a discrepancy between the moon's real position and that which it ought to have, as given by the horizontal circle on B.

turning the dial and earth round on the axis, and keeping his eye in the plane of the former, he may observe the moon's rising and setting, and the hour at which it happens, and, in short, with care and skill he may acquire correct notions of the cause of all the lunar phenomena.

In conclusion we would observe, in answer to those who might consider the subject and our mode of treating it too elementary for our Magazine, that although it may not interest them personally, yet as no child could make or adjust such an instrument without assistance, and as every one is directly or indirectly interested in the instruction of young people, the paper and the toy it describes are not so inconsiderable as they might at first appear.

THE PROGRESS AND STATE OF SCIENCE IN BELGIUM. In our opening number we announced our intention of specially devoting a portion of our Journal to the communication of whatever might appear most generally interesting in Foreign Science, and especially from time to time to give such abstracts as we might be able to obtain of its general condition in the several countries of Europe.

This pledge we have partially redeemed by the various notices we have inserted, referring to foreign discoveries and researches. We hope to fulfil the same promise to a greater extent in the present article. We have been kindly favoured with a copy of the Bulletin of the Royal Academy of Sciences at Brussels, containing the detailed proceedings of the public Séance of Dec. 16th, 1835; and shall present our readers with what has appeared to us the truly interesting Report, delivered on that occasion by the perpetual secretary, M. Quetelet.

In doing this, we have thought it best to adhere closely to the author's own words, and, instead of attempting any compilation of our own, to present his luminous and often eloquent views in a translation, if not always strictly literal, yet always following the tenour of his reflections. We think it right to apprize our readers of this, in order to account for an occasional style of expression which would not perhaps be adopted by an original English writer. This, however, we do not doubt, will rather be regarded by our readers as characteristic, and as only tending to bring more vividly to their minds the actual tone of scientific views at present prevailing in Belgium. Without further preface then

we commence.

Report of the Permanent Secretary on the Labours of the ANCIENT IMPERIAL AND ROYAL ACADEMY OF BRUSSELS.

In some introductory remarks, the distinguished author gives a rapid sketch of the progress of arts and sciences in Belgium in former centuries:-their flourishing condition under Charles V., and subsequent decline, and almost total extinction. The dawn of a better state of things, however, approached:

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It was under the auspices of Maria Theresa, of glorious memory, that the Imperial and Royal Academy of Brussels was formed. The few

really well-instructed men that Belgium contained, united themselves with several foreigners of distinction, and the language of science was once more heard amongst us.

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The labours of this learned body were crowned with a brilliant success, and obtained great favour with the nation, who well understood that the opinion that would be formed of her by foreigners, would henceforth depend on the esteem in which an assemblage of men would be held, who might be considered as her representatives of national intelligence. Unhappily, this success was of short duration.

"A revolution, which broke down the greater part of the props of the ancient social edifice, and renewed the political constitution of many states, also changed our destinies.

The Academy of Brussels was suppressed; its members were dispersed; and when, at a later period, we became a part of the great body of the French empire, of which the whole intellectual life appeared concentrated at Paris, it might be asked with reason, whether Belgium had not again fallen into its ancient state of torpor.

"The Imperial and Royal Academy of Brussels, whose important services are to this day too little appreciated amongst us, appeared then but for an instant, and as a prelude to a new era which was soon to open before us, and to restore to us, with our ancient liberties, our former taste for the arts, literature, and science. When in 1816 this learned body was re-organized, the few members who were yet living, were called upon to compose it; but some had expatriated themselves, and others were for the most part too aged to be able a second time to co-operate in the intellectual regeneration of their country. At the present time these men of another age have successively become extinct.

"The new academy, in creating an annual public session, was desirous of consecrating the memory of the 16th of December, the day on which the ancient Academy of Brussels was founded, and which, by a happy coincidence, is also the birth-day of our august monarch; and they have deemed that they could not with 'more propriety usher in their public session, than by giving a rapid sketch of the labours of its predecessors, as constituting the finest eulogium that could be offered to their memory.

"It is to me that has been intrusted the honour of paying this tribute of gratitude,—this sacred debt, which is indeed also that of the nation.

“I will not here stop to retrace the origin or the first labours of the Academy, the recital of these may be found detailed in the volumes which commence the former, and the new series of our memoirs.

"I shall only speak of its foundation, with a view to make that character of grandeur and magnificence which was imprinted on it, and which would do honour to the most enlightened governments, duly appreciated. Its august foundress had well perceived, that in order to restore the sciences in a country where they had nearly fallen into complete oblivion, it was necessary to encircle with honours, and worthily to recompense those who cultivated them with success. She constituted the Prince of Stahremberg her minister plenipotentiary to represent her in the Academy, in the capacity of protector; and the chancellor of Brabant was invested with the presidency. The royal library was assigned as the ordinary place of assemblage. The Academy had moreover the enjoyment of that rich collection, which had formerly belonged to the duke of Burgundy: permission was granted it to use as its great seal the arms of that illustious house, and thus of associating its name with those of the brightest recollections of our national history. Funds were liberally accorded for the printing of the memoirs, for remunerating contributors, and

for scientific travels.

Pensions were created in favour of superannuated members, or for such as had distinguished themselves by their activity.

"Lastly, to give a further mark of the particular esteem that we accord to useful talents, and to those who cultivate them with success,' said the empress in her letters patent, we decre that the quality of academician shall communicate to all such as shall be decorated with it, and who shall not be already ennobled by their birth, the distinctions and prerogatives appertaining to the estate of personal nobility, and this in virtue of the act of their admission into this society.'

"If we quote these words it is not to attach importance to ancient prerogatives, but to give a clear understanding of the powerful assistance which science received at a time when these prerogatives were everything in the eyes of the world.

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The academy, however, received a still higher privilege, an inestimable benefit for the learned,-I mean the liberty of the press, that mother of thought, which then appeared as a consoling phenomenon, on emerging from our long night.

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So many combined advantages would naturally create an ambition of being an academician; thus a noble emulation spread throughout Belgium, and it was not long before talents were seen to arise, which would have remained stupified without stimulants of such energy. Five volumes of memoirs were published by the Imperial and Royal Academy of Brussels, during its short existence; as were also many volumes of prize-memoirs. A detailed analysis of these scientific and literary works would perhaps become tiresome, but it may be interesting to examine into the useful consequences they were of to Belgium.

"If we consider, for example, the physical sciences, we shall observe, that in order to judge of their advancement in a country, one may take for a standard, the height to which the study of mathematics has been carried. Mathematics is the language in which natural phenomena are expressed, and valued numerically, when they have been duly studied and reduced to their most simple elements; and in general, the difficulty which most branches of science experience in having their phenomena translated into this language, only tends to show the feeble degree of advance they have made.

"In adopting a like scale we find since the date of the earliest publications of the old academy, an immense progress in Belgium. In fact, the birth of the infinitesimal calculus had, as we have already said, followed close upon the decay of science in our provinces; it had attained the most rapid growth, and that all-searching instrument, the powers of which were tried by removing, as if by enchantment, the thick veil which covered the finest secrets of the system of the world, had not even attracted the attention of Belgium. After having reduced, if one may so speak, the heavens within its dominion, the infinitesimal calculus had made the happiest excursion through the fields of physics, and attacked directly the most beautiful problems of that science, in which we were yet studying works that were quite out of date.

"The commandant of Nieuport, in the second volume of the Ancient Memoirs of the Academy, was the first to show that the higher branches of analysis had found an interpreter in Belgium: he at once accomplished the solution of many important problems with which geometers were then occupied, and his labours put him in communication with d'Alembert, Bossut, and Condorcet. Such relations not only do honour to the learned person who is the object of them, but also to the country to which he belongs.

"So fine an example hardly found any imitators. Mr. Bournouns was the only one in the Academy, and one may say in Belgium, who occupied

himself with researches of the higher analysis, but with much less success than the commandant of Nieuport. The ancient university of Louvain, in its course of instruction, scarcely went beyond the rule of Cardan for the resolution of equations of the third degree; and as for astronomy, it still held to the vortices of Descartes, although many of its professors began to occupy themselves with the laws of attraction. As for astronomical observation, it absolutely did not exist; it was to foreign men of science, who associated themselves with the first labours of the academy of Brussels, that the only observations really worthy of having been made in this country, are due: these have been registered in our ancient memoirs, where we meet with the names of Messieurs Pigott, the Count of Bruhl, the Baron Zach and Lalande. When this last astronomer made the circuit of Europe to visit the observatories, he did not dissemble his astonishment at not finding amongst us any traces of his favourite science. 'In the Austrian Netherlands, now French,' he writes, astronomy does not appear to have been cultivated :' he then adds, 'the only observer of this country is an English gentleman of the name of Pigott.' This learned person is indeed established among us, and he made at Louvain, Brussels, Ostend, Tournay, Luxembourg, and Hoogstraeten, various observations on the satellites of Jupiter; he also took the meridional altitudes of a great number of stars, by means of one of Bird's Quadrants, which had been intrusted to him by the Royal Society of London. These observations were undertaken with a view of co-operating in the construction of a good map of the country, which was desired by the government,-a map which at the present day is so much wanted, and which forms a blank, but little honourable it must be confessed, amidst those geodæsical labours which have been accomplished by our neighbours.

"It was, again, the ancient academicians of Brussels, who contributed to spread in Belgium with the greater ardour the novel and brilliant discoveries of the physical sciences; nor were they rendered less useful by the applicability of their knowledge to the study of our own country, with which they were occupied with the greatest zeal; and it is that which makes the collec tions of our memoirs so precious to the learned, who may wish to study our provinces in a scientific and literary point of view. Amongst the members who most distinguished themselves in the physical sciences, must be mentioned the Abbés Mann, de Needham, de Witry, and Dr. Godart. The first of these in particular was remarkable for the diversity of his works; it is true they must not be considered, even with reference to science, as being very profound, but ingenious views, and sometimes the most happy conceptions are there found. Thus this learned man has well hit upon the relations which exist between the appearances of the aurora borealis, the movements of the magnetic needle, and the quantities of atmospheric electricity, affinities which have so much engaged, in these latter times, the attention of the most distinguished natural philosophers. He had likewise formed very correct notions on the method that should be pursued in the study of meteorology, a science in which but little advance has been made in our time, notwithstanding all the labours that had been undertaken in order to accelerate its progress. The Palatinate Meteorological Society had just been organized at Manheim, and addressed itself to the principal learned bodies in Europe, to ask their co-operation in the vast system of combined observations which it proposed to execute; it also addressed itself to the Academy of Brussels, and the Abbé Mann was selected to answer the appeal of the learned Germans. He acquitted himself honourably of his mission; and even now his observations are consulted with profit, and cited in most treatises on natural philosophy. Many other members of the academy occupied themselves equally with

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