The latter table contains the mean motions of the planets in longitude for a period of 100 years in respect to the equinoxial points; but which motions are, however, subject to a secular variation, arising from their mutual attractions. The solar or tropical year is consequently a variable quantity for all the planets but their periodic times in respect to the fixed stars; and the greater diameters of the planes of their orbits, was the same a million of years since, and will be the same a million of years hence, as at the present time.

The secular precession of the equinoxial points at the present time is 1° 23′ 30′′. The above period contains ten revolutions of the precession, with a mean secular motion of 1° 26' 5" in a century; but I cannot, at present, state whether this comes within the limits of the secular variation. If so, the siderial periods of the planets will contain ten revolutions less, and the tropical periods of the satellites ten revolutions more, than are given in the above tables.

In respect to the variation of the obliquity of the ecliptic, Laplace states the maximum variation at 1o 21', which is the extent of the oscillations on either side of the mean obliquity, 2° 42′ being the total extent of the variation. One period of the oscillation is completed in 41,817 years; consequently, six oscillations are performed in 250,904 solar years, which gives 46".4879 for the mean secular variation of the obliquity, which agrees extremely well with modern observations.

A singular approximation presents itself between the siderial periods as above stated, and those given by Mr. Baily in his tables, in respect to the satellites of Saturn and Uranus. In my tables, the decimals are extended to two places of

figures more than are given in Mr. Baily's, and in ten cases out of thirteen, the last two figures are cyphers, but which are all given to the nearest unit, having been computed to ten places of decimals by dividing the 91,640,740 days by the number of revolutions of each planet respectively! Now for a word or two as to theories. We have recently been presented with a liberal supply of theories to account for the effects produced by what, in the Newtonian theory, is termed gravity or attraction; and likewise to account for the stratification of the exterior crust of the earth, the origin of the different substances of which the earth's surface is composed, &c.

In respect to the first, we see the effects produced, but the cause, or by what means these effects are produced, remains a myslery; which will, I predict, be discovered much about the same time as the philosopher's stone and the perpetual motion! I am not, however, going to enter a discussion of the above subjects at the present time, but merely to offer a few remarks on the effects pretended to have taken place in consequence of either the motion of the equinoxial points, the earth's perihelia, the obliquity of the ecliptic, or the excentricity of the earth's orbit.

It has been contended by different theorists, that the various stratas that compose the earth's surface, have been deposited by the alternate revulsion of the waters of the ocean from the north to the south pole, and vice-versa. Now, in regard to the motion of the equinoxial points, it is very well known to astrono mers, that the apparent situation of the fixed stars are constantly changing; their longitudes and right ascensions being reckoned from the first point of Aries, but which point is not stationary in respect to

the fixed stars, owing to a retrograde motion of the equinoxial points, which occasions the solar or tropical year to be about 20 minutes of a degree shorter than the siderial year, or revolution of the sun in respect to the fixed stars. For the correction of the equinoxial points in right ascension and declination, see my tables in the 1st vol. of the Rev. Dr. Pearson's Practical Astronomy, pp. 281-286.

The present Polar star, according to Leadbetter, will in the year 15064, be 8° 56′ 49′′ south of the zenith of London. Now, it is a mistaken notion altogether, to suppose that the latitudes or longitudes of places on the earth's surface vary from this circumstance, as there has not been the least variation in the latitude of places in respect to the Poles, discovered from the remotest period to the present time. It being in the right ascensions and declinations of the fixed stars in which, in this case, the variation is apparent.

The perihelion point of the earth's orbit is that in which it is nearest the sun. The aphelion is, consequently, the point in which the sun is farthest distant from the earth; the line connecting these two points is called the line of the apsides, which is not stationary, but has an annual motion of 11.8 in respect to the fixed stars; but in regard to the ecliptic, it has an annual motion of 61".9 on account of the precession of the equinoxes. The motion of the perihelion point will not influence the waters on the earth's surface, or give them a tendency to accumulate more at one pole than the other; it is true, the sun is nearer when in perihelion than in aphelion, and has a greater attractive power in one case than in the other; but this is occasioned by the excentricity of the earth's orbit. If the orbit of the earth was a circle, the line of the apsides would vanish, and there would be no aphelion or perihelion points.

In regard to the obliquity of the ecliptic, it has been demonstrated, as before mentioned, that the variation of the obliquity is confined within narrow limits, and which is occasioned by the mutual attraction of the planets. The earth being protuberant at the equator, the sun has a greater attractive power on that side of the earth which is nearest him, than he has on the other side, which is more remote, on account of the difference in the distance, or nearly equal to the earth's diameter. Consequently, the excess of the

sun's attraction will have a tendency to bring the equator more under the sun, in opposition to the attractions of the planets in a more oblique direc'ion to the plane of the equator. Besides, were the sun perpendicular at the poles, there would still be no perceptible difference in the tides; as we have frequently higher tides in the winter, when the sun's altitude is least, than we have in summer, when his altitude is greatest.

The excentricity of the earth's orbit is at present diminishing, and will, probably, continue to do so till the orbit of the earth becomes a circle; after which, the excentricity will again increase to a certain amount (being confined within narrow limits); but the period of this variation includes, as well as that of the moon's acceleration, millions of years. The acceleration of the moon being produced in consequence of the diminution of the earth's excentricity, on which it is dependant. When the earth is in perihelion, it is about three millions of miles nearer to the sun than when in aphelion, and yet we observe no perceptible differrence in respect to the tides.

The only circumstance which could effect a transmission of the waters from one pole to the other, is an alteration in the direction of the earth's axis of rotation, or in its polar diameter; and, consequently, new equators would be acquired, to which the waters would accumulate from the effects of the earth's centrifugal force; and thus, by a shifting of the axis of rotation, would cause an elevation of the waters in succession from the North to the South Pole. But that this circumstance never took place, is evident from the known figure of the earth and planets being oblate spheroids, which, in all probability, took this form from the effects of their rotation, when in a liquid or soft state.

The planes of the equators of the earth and planets cut through the centres or middle of these protuberances at right angles to their polar axis. Hence, it appears evident that the planets revolve on the same axis now, as they did previous to their being in a consolidated state. That the surface of the earth has undergone numerous mutations, is evident; but which could not have been effected by a slow and tardy motion, like that of the shifting of the earth's axis. The greatest revolutions on the earth's surface, appears

to have been caused by some internal convulsions, by volcanoes, or earthquakes.

As there has been numerous blocks of stone found on the earth's surface, some forty or fifty miles from their parent rock, may not some three or four of Mr. Mackintosh's moons,* which were originally attendant on the earth, have fallen to its surface and broken into fragments? This would account for the abrupt and rocky appearances of various places on the earth's surface. But, by-the-bye, I cannot see, as he

says, "the earth was formerly much larger than it is at present," how it can be smaller now, after the acquisition of these three or four moons, than it was originally! A very copious discharge of the electric fluid from the earth would be required to sweat it down from its original, to its present dimensions!!

In conclusion, I beg to observe, that the above period of conjunction may be objected to on account of the length of time occupied in its completion. It appears from the latest discoveries of geologists, that the revolutions which the earth has undergone, must have occupied a much longer period of time than that assigned by Moses, for the creation of the world; but this does not militate in the least against the testimony of Moses, as he does not say that the earth was then created, but that "it was without form and void, and darkness was upon the face of the deep" from which it appears the earth was in existence previous to the time to which he alludes; and might, probably have undergone some dreadful catastrophe, which destroyed all its former inhabitants, if any existed. As there are hundreds of valcanoes in an active state of ignition at the present time, and also a great number which have become extinct, may not their origin have been occasioned by a general conflagration? or how are we otherwise to account for so many burning mountains dispersed over the earth's surface?

If a conflagration is admitted antecedent to the creation of man, as recorded by Moses, a great part of the waters which now cover the earth's surface, would, by the intense heat of the earth, have been converted into vapour, and suspended in the atmosphere, which, together with clonds and smoke, would have obscured the sun, whence darkness would have been on the face of the deep,

* Mechanics' Magazine, vol, xxiv, P. 234.

as related by Moses. We are also taught to believe that the world will, at some future period, be destroyed by fire; but it is not probable that the earth will be annihilated, as it may, after this catastrophe, be rendered a more delightful residence for a future race of intelligent beings than it is at the present time.

We have the greatest reason to suppose that the fixed stars are suns, attended by planetary bodies, with their attendant satellites or moons, similar to those of our system; and that they are, in all probability, inhabited by intelligent beings, of whose nature and constitution we can form no conception, as the Almighty has made nothing in vain. Of his kingdom there is no end, neither as to time or space. As an illustration, suppose the number of fixed stars, visible in our best telescopes, to amount to one hundred millions, exclusive of their attendant planets and satellites, and that the Almighty had created as great a number of systems as above stated, in every second of time, during a nonilliont of years, they would still be very far short of occupying one nonillionth part of infinite space, admitting them all to be placed at the same distance from each other as the fixed stars!

There may be stars placed at a distance from us so remote, that a body moving with a volocity of a nonillion of miles in one second of time, would occupy a nonillion of years in passing from them to our earth!! These numbers are, however, far above our comprehension, it being impossible for finite beings to compre hend infinity.

I am, Sir, Yours, &c,
JAS. UTTING, C. E.

Lynn Regis, Dec. 20th, 1836.

SIR JOHN SOANE'S MUSEUM. It has been already stated in the Me chanics' Magazine, that the splendid museum and library of the late Sir John Soane have become vested in the nation by his decease. By a clause in the Act of Parliament, by which Sir John was empowered to carry his intentions into effect, it was, however, provided that in case he should choose to leave his collection, by will, to the British Museum, there to be preserved separately, with the title of "The Soane Collection," the house in Lincoln's-inn-fields, together with the

† A nonillion is a million nine times repeated; its value is equal to unity followed by 54 cyphers.

proposed endowment for the support of the Museum, should be considered a part of his private estate, and descend to his heirs, instead of to the nation. We believe the purport of the will is not, at present, known; but it is most probable that the original intention of Sir John, as developed in the Act of Parliament, will not have been interfered with by its provisions; and that, consequently, the mansion, as well as its contents, may now be looked on as public property.

It seems, by no means, to have been intended by the donor, that admission to his collections should be granted to the public as liberally as is now the case at the British Museum. The Act directs, that "free access shall be given at least two days in the week, in the months of April, May, and June," to

amateurs

and students in painting, sculpture, and architecture, and to such other persons as shall apply for and obtain admission thereto, at such hours, in such manner, and under such regulations, for consulting and inspecting, and benefitting by the said collections, as the said Sir John Soane shall have established previous to his decease." From this it will appear how erroneous is the prevalent idea, that the restricted admission granted by Sir John during the last two years; was merely provisional: and that as soon as the Museum became public property, the public were to be admitted to it as freely as to the pre-existing national establishment. It may be remarked, however, that the trustees have the power to establish new regulations, and that, if they do, they will most probably tend to the increase of facilities of admission. If it become the regular state of things for the Museum to be open only two days in the week, for three months in the year, and that only to the select few who are able to procure tickets of admission, it will be a public institution in name alone.

There would be no pecuniary difficulty in the way of affording more extended admission, as the Act empowers Sir John to invest 30,000l. in the public funds; out of the interest of which, the "Curator" of the institution is to be paid a salary of 3007. per annum, in addition to which, he is to reside rent-free in the mansion. The Act provides, that the curator shall be appointed (after the first, who is to be named in Sir John's will) by the Council of the Royal Academy, and that

he must be "an English architect, who shall have distinguished himself, or gained a prize." The trustees are partly to be elected by the survivors of the original trustees named by Sir John, with the addition of five elected respectively by the Lord Mayor and Aldermen of London, the Royal Academy, the Royal Society, the Society of Arts, and the Society of Antiquaries. Of course, should the collections have been left to the British Museum, all these provisions will be cancelled.

The exterior of the "Soanean Museum" is pretty well known to the London public of the interior they know but little (and are likely to know little, if the restrictive directions of the Act be too closely complied with), except from the work devoted to its illustration, published a year or two ago, by Mr. Britton. At the latter end of 1835, Sir John Soane himself also privately published a work of the same description, with numerous em bellishments, from which a general idea of the Museum and its contents may be gathered. The arrangement of the interior would seem to be a curious amalgamation of the private gentleman's residence with the public museum. Thus, one of the principal apartments combines in itself the characters of dining-room and library; the "Sepulchral Chamber" is in rather close contact with the breakfast-room; and picture-rooms and bedchambers, dressing-closets and modelrooms, &c. &c., are jumbled together in most admired disorder. As the mansion, even when thrown open, is still to be the residence of Sir John's grandson, we suppose the restrictions as to access, which have been alluded to, were dictated by a wish to preserve his domestic comfort, which might indeed be seriously compromised, if the public were to use the same apartment for a library which he required at the same time for a diningroom!

The great "lion" of the collection, it is well known, is the Sarcophagus, brought over by Belzoni, from Egypt. It is of alabaster, of exquisite workmanship, and literally covered with hierogly phics. It was offered, after it had been publicly exhibited for some time, by Belzoni's widow, we believe, to the British Museum. For what reason, it is not stated, the authorities of the Museum refused to purchase, and Sir John Soane immediately after became its pos