ments.

The turnpike acts, for instance, would in most cases be eluded; and the post-horse duty would be likely to become unproductive. Impositions, however, as well as improvements would be likely to take place as the system advanced. Any smoke which proceeded from the furnace of the vehicle would, converted into gas light, serve in time to direct its progress. The heat of the fire might, perhaps, be a little inconvenient in summer; but (to outside passengers especially) in winter it would be an advantage. And, with respect to the possibility of an occasional blow up, there can be no doubt, that as soon as the scheme gets into practice, any one of the insurance companies, for a reasonable premium, will guarantee, at per mile, the lives of steam passengers; and such insurance might either be made matter of separate contract by the individual, or it might be done generally by the coach proprietor, and included in the fare.

NEW GOLD MINE.-A mine of gold has been lately discovered in Georgia, which has proved richer than any hitherto known; for, in a single day, the produce of the labours of seven miners yielded no less than forty pounds sterling, in value of pure gold. The surface of this mine consists of hard rocks.

COUNTERFEIT GoLp.—A German, Dr. Hermstad, has discovered a mixture of metals, which is not only of the colour of real gold, but also possesses its hardness, all its ductility, and the same specific weight. The inventor, however, does not assert that it is as unchangeable as gold; and there can be no doubt that if he had met with that quality in it he would not have failed to mention it; for in that case he would have found the secret which has been so long and so vainly sought by the alchymist. This material is thus composed :-Out of twenty-four parts, equal in weight, there are sixteen of platina, seven of pure copper, and one of pure zinc; this is to be covered with powdered charcoal, and placed in a crucible, on a strong fire, until the fusion has reduced the three into one mass, which will be the said counterfeit gold.

INTERESTING RESULTS FROM LAUREL OIL AND ALCOHOL. —A remarkable circulating motion is observed when laurel oil and alcohol are brought together. Take a phial of the laurel oil, and drop into it, at different intervals, some rectified spirits of wine, when the most interesting results will be observed to ensue-a circulation, presently commencing, of globules of alcohol up and down through the oil, which will last for many hours or for days. A revolving or circu

lating motion also appears in the oil, carrying the alcoholic globules through a series of mutual attractions and repulsions; the round bodies moving freely through the fluid, turning short in a small eccentric curve at each extremity of their course, passing each other rapidly without touching, but after a time they seem to acquire a density approximating to that of the lower stratum, which appears to be an aqueous portion separated by the ethereal oil from the alcohol; and this assimilation taking place, the globules, after performing many revolutions, will fall flat upon the surface and unite with the lower or watery stratum. This experiment was performed with a small phial: perhaps a larger one would render the result more perspicuous.

SILK FROM COBWEBS.-At a late meeting of the Society of Arts, a gentleman exhibited some very fine silk which he had obtained from the web of the spider; it possessed considerable strength, and a beautiful metallic lustre. Many species of spider have been tried, and food of a varied character given to them—the larvæ of flies successfully.

ACOUSTICS.-Captain Parry, in his Third Voyage, p. 58, relates that a conversation could be distinctly carried on at Port Bowen, at the distance of 6,696 feet. Dr. Clarke, however, mentions a more extraordinary instance of the propagation of sound. He asserts, vol. iii. p. 331, that while sailing from the Gulf of Glaucus to Alexandria, the firing of the English, in attacking the fortress of Rachmanie upon the Nile, was distinctly heard by all on board, a distance of 130 miles.

INVENTOR OF THE SPINNING WHEEL.-The "Schwerin Evening News" reproaches the manufacturing world with ingratitude, because they have failed to consecrate an hour of the past year to celebrating the third centenary of the birth of Jurgeas, the Wolfenbuttel stone-mason, who invented the spinning wheel for flax.

TO PRESERVE EGGS.-Why are eggs preserved by rubbing them with butter? Because the butter closes the pores in the shell, by which the communication of the embryo with the external air take place; the embryo, is not, however, thus killed. Varnish has a similar effect. Reaumur covered eggs with spirit varnish, and found them capable of producing chickens after two years, when the varnish was carefully removed.

AN INQUIRY AFTER HAPPINESS.

No lowering cloud obscures the sky,
Nor ruffling tempest blows.
Now every passion sinks to rest,
The throbbing heart lies still;
And varying schemes of life no more
Distract the labouring will.

In silence hushed, to Reason's voice
Attends each mental power;
Come, dear Emilia, and enjoy
Reflection's favourite hour.

Come, while the peaceful scene invites,
Let's search this ample round;
Where shall the lovely, fleeting form
Of Happiness be found!

Does it amidst the frolic mirth

Of gay assemblies dwell?
Or hide beneath the solemn gloom
That shades the hermit's cell?

How oft the laughing brow of joy
A sickening heart conceals!
And through the cloister's deep recess
Invading sorrow steals.

In vain through beauty, fortune, wit,

The fugitive we trace;

It dwells not in the faithless smile

That brightens Clodio's face.

Perhaps the joy to these denied,
The heart in friendship finds?

Ah! dear delusion, gay conceit
of visionary minds.

Howe'er our varying notions rove,

Yet all agree in one,

To place its being in some state
At distance from our own.

O blind to each indulgent aim
Of power supremely wise,
Who fancy Happiness in aught

The hand of Heaven denies !

Vain are alike the joys we seek,
And vain what we possess,
Unless harmonious Reason tunes
The passions into peace.

To tempered wishes, just desires,

Is Happiness confined,

And, deaf to Folly's call, attends

The music of the mind.-MRS. CARTER.

ON THE TIDES. Of all the phenomena of our planet, there are not many more difficult to explain than the cause of the flux and reflux of the sea. To this important subject our greatest astronomers have directed their attention; to all the theories hitherto advanced there are insuperable objections. In the earlier periods of science, it does not appear that any conjectures were ever indulged in as to the cause; this may in part arise from the philosophers whose works have been transmitted to us principally residing on the borders of the Mediterranean, where the influence of the tides is very trivial. Homer, speaking of Charybdis, says, "Thrice each day it rises." Charybdis is only a whirlpool in the straits of Sicily. Horace mentions tides as a phenomenon he had heard of: "Quæ mare compescant cause. In the Syrtic and Adriatic, in the faro of Messina, and the Euripus, Dr. Shaw particularizes tides; the two¡latter are merely currents.

Pytheas, of Marseilles, who lived about the time of Alexander the Great, states his opinion of the tides being governed by the moon. We had no demonstrations attempted before the period of the celebrated Des Cartes, who introduced his "System of Vortices" to explain the principle of regulation by the moon's motion. Kepler, who first suggested the influence of a gravitating principle in nature with respect to the cause of the tides, entertained an extravagant supposition of the earth being a living animal, and the flux and reflux of the sea the results of the action of respiration. Galileo supposed tides to be produced by the different velocities of the annual and diurnal motions of the earth; if so, the tides should occur at the same periods, without variation in their rise; but they are observed to move through the twenty-four hours, and vary daily in their elevation. The illustrious Newton, in his Principia, has stated his opinion that there is an attractive power existing between all bodies in proportion to their quantity of matter, and the inverse duplicate ratio of their distance; and hence has reduced to geometrical demonstration the varied influence of the moon as she moves in her orbit, how the tides are governed by her nearest and most remote distance from the earth, the changes observed from the different inclinations of her orbit to the ecliptic, and from the irregular motion of her nodes. Whether such a force or power be hypothetical or real, I presume that the geometrical demonstration will not be affected. If gravitation be not admitted as a principle competent to explain the phenomena, we

must substitute some other agent capable of producing all the effects observed.

Supposing the mean distance of the moon from the earth to be sixty times the radius of the earth, and if the law of gravitation be assumed, according to Newton, as diminishing as the square of the distance increases, it will be evident that 60 multiplied by 60, being equal to 3600, will express this proportion, viz. that 3600lbs. on the surface of the earth, removed to the moon's surface, would only weigh one pound. As the waters of the ocean are the only part of our planet susceptible of any change from such an influence, the tendency of the waters of the ocean towards the centre of the earth will be in the same proportion diminished. Let us suppose the gravitating powers of the waters of the ocean, when under the direct influence of the moon, to be diminished in this proportion, viz. one-sixteen hundredth part. From the law of pressure, with respect to liquids, the action is equal in every direction, and which action is attributed by Newton to the power of gravitation being uniform; if this power be disturbed in any part, there will be a determination of water to that part, till the equilibrium be restored, and the elevation of waters in that part will constitute the tide. Let us suppose the mean depth of the ocean four miles; thus, one-sixteen hundredth part of this being elevated, will be about six feet. Newton does not confine the diminution of gravitation in the water of the ocean merely to the influence of that luminary; he supposes a co-operation of the sun, which he concludes, from its quantity of matter compensating for its greater distance, produces an effect about onethird of that of the moon; so that when combined, as in a new moon, their united effects would, under such circumstances, produce an elevation of eight feet. When the moon is in her quadratures, i. e. when she appears to us as a half moon, then they counteract each other, and the tide will be proportionate to the difference, viz. by the above supposition, four feet, constituting what is denominated neap tides.

These admeasurements are only assumed for the purpose of illustration. It is well known that at the same period there is a spring tide at new moon, at the nadir, as well as at the zenith, part of the earth; this presents the greatest difficulty to the Newtonian theory. If, according to the Newtonian hypothesis, an elevation of those waters, which are in a direct line with the moon at or near her meridian, is to be referred to the cause aforementioned, the same hypothesis is extended to account for the tides on the opposite side of the globe, to the earth itself being attracted from the