All the different varieties of the lavas of Vesuvius may be found here apparently in a rapid progress of decomposition, so that at some future period this island, like other volcanoes, will be one mass of rich mould. Many of the round conical hills are already fit for being planted with vines; their soil being composed of ashes and a ferruginous earth, a decomposition of calcined ores of iron: of this description is Red Cross Hill, near the anchorage, having an elevation of 870 feet above the sea; but so dry and porous is the soil, that no sooner does the rain fall than it is absorbed and disappears.

The principal cultivation is on and about Green Mountain, where it rains more frequently than on the less elevated parts of the island. The principal garden is 2,500 feet above the sea: here the climate is delightful, the temperature during the day time being generally about 74°, that at the landing place near the fort being 85°. The temperature on the peak is still lower; my thermometer exposed to the current of air sweeping over the peak fell to 60°, this was at one P.M., the instrument being in the shade, and the sun shining at the time. The summit of Green Mountain is covered with rock roses and several species of fern and mosses, indigenous to the island. There may be about 100 acres of land already cultivated, (1830,) and about 1,000 more fit for cultivation by the plough, on and about Green Mountain, independent of many ravines and hollows containing a rich soil, where no doubt fruit and other useful trees will be planted, so soon as the different fortifications shall be complete.

The climate of Ascension is perhaps as healthy as in any part of the world, and its salubrity is no doubt owing to the constant trade wind blowing in a moderate breeze, ventilating and cooling every part of the island; the dryness of the air, and the absence of marsh or moist soils, contribute to the elasticity and buoyancy of the air, and renders the island a most desirable spot for an invalid, who might be transported from Tartar Stairs to the mountain in two hours, the distance being seven miles, from a temperature of 81° to one of 74°.

Abundance of purslane grows among the rocks, stones, and crevices of the cliffs; this vegetable is eaten by the cattle, and is capable of keeping them alive and in tolerable condition, as was evident from a bullock making his escape, and being absent five or six months, during which time he had nothing to eat but purslane.

The animals that are found in a wild state are rats, cats, goats, and land crabs: the cats are numerous, but instead of destroying the rats, they take up their abode in the neighbourhood of places frequented by the different species of sea fowl that visit the island. The goats, rats, and land crabs are great enemies to farming, destroying all sorts of plants and fruit; they are, therefore, killed in great numbers by the garrison, and may ultimately be extirpated.

The weather side of the island is high and inaccessible, with an iron bound coast, and deep water. No part of the coast is accessible from South-west Bay round the south point of the island, and as far as North-east Bay.

From the south point of South-west Bay, and along the lee side of the island to English Bay, there is an excellent anchorage in from ten to twenty fathoms water, sand and mud, within the distance of six

miles, three hundred sail might be anchored at the distance of 100 fathoms from each other, for although the coast from the fort round to South-west Bay be rocky with foul ground extending about half a mile into the sea, as marked on the chart, yet I found the bottom perfectly clear, without the depth of ten fathoms.

I have already stated that upwards of forty craters have in former times been in a state of activity. Now the island lying within the limits of a constant brisk south-east trade wind, the ashes and pummice dust, &c. ejected by the volcanoes, have been carried by the wind into the sea to leeward of the island, and formed an excellent anchorage: the bank thus formed has in the course of time been augmented by vast quantities of small shells ground up together, and polished by the action of the waves; and it is those fine pieces of shells that form the various beaches on the lee side of the island where the sea-turtle deposits her eggs to be hatched by the heat of the sun.

Wherever there is a prevailing current in the air or ocean, at an island, the dust in the air, or the mud in the sea, is carried by the current and deposited to leeward, where a bank is formed on which ships may anchor; this is the case at St. Helena, Ascension, the Madeiras, the Canaries, and Cape de Verd islands, &c.

Ascension is visited by the sea-turtle between Christmas and Midsummer, and it is supposed that during the above period each female makes three or four nests. The animal remains on the coasts of the island till fifty or sixty eggs are fit for being deposited in the sand. She then lands on the beach, between ten o'clock at night and four in the morning, and going sometimes 150 or 200 yards above high-water mark, digs a large pit about eight or ten feet in diameter, and two or three feet deep, where the eggs are deposited and carefully covered with sand; she then leaves them to Nature. In about nine or ten weeks the young turtle breaks its prison, and working its way upwards through the sand gains the surface, and proceeds directly to the sea. Should this journey happen in daylight many of the young animals are picked up and devoured by the man-of-war bird, who may be seen hovering over the turtles' nests. For this species of warfare in destroying the young turtle, the man-of-war bird is shot, or otherwise destroyed by the officers of the garrison.

There are abundance of excellent fish to be caught among the rocks throughout the year, such as rock cod, conger, cavalhois, &c.; they are so plentiful that a boat's crew may catch enough for a frigate's ship'scompany. The best place for fishing is on the reef near the anchorage, beginning with a piece of salt pork for a bait, and afterwards cutting up fish for bait. Cray fish are also caught near the mouths of caverns among the rocks towards English Bay, the method is as follows:Hang a piece of fish or pork by a string a short distance below the surface of the water at the mouth of a cavern, the cray fish observing it will rise to the bait, and may be taken by hand.

The coast to leeward of the island is bold and clear from English Bay to the fort near Tartar Stairs. About a mile to the north-east of the fort there is a small bay with a spot of sand on it, on which a boat may land among wild and irregular climpers: this spot has been dignified by the name of Comfort Cove, and extolled very much above its

real merit. From the foot of Fort Cockburn round to the westward as far as South-west Bay, the coast is, as has been already observed, rocky. The reef runs out about seven-tenths of a mile from the fort in a northwest direction, it is composed of uneven masses of hard pointed lava with spots of white sand in the hollow places; there are many of these pointed rocks on which a ship would strike, and on some of which ships have actually struck; and to prevent such accidents for the future a large buoy is now moored near the extremity of the reef on a rock having thirty feet water on it-the following are its marks :-The flagstaff on the fort in a line with the north-east corner of the jetty, near the crane at Tartar Stairs, and the peak of Green Mountain just touching the edge of Red Cross Hill. Should the buoy be gone by keeping in ten fathoms a ship will avoid all the dangers on the reef.

It sometimes happens that a very heavy swell sets in from the southwestward occasioned by gales of wind without the limits of the trade winds in the South Atlantic. The long swell rolling in against the wind, and meeting with shoal water, and the uneven rocky bottom of the reef breaks high, and with violence, sweeping away thousands of tons of sand from the beach into deep water: this sand is again thrown on shore in fine smooth water.

These rollers are heaviest when the sun is in the Northern Hemisphere, and storms and tempests in the South Atlantic, in the neighbourhood of Cape Horn.

Two pair of moorings are laid down near the landing-place for the use of H.M. ships: one pair abreast of the middle of the sandy bay to the eastward of the fort, and as near the weather shore as possible. The groundwork is line-of-battle ship's chain, and the bridles are tapered from line-of battle ship's chain to sloop's; the small end being suspended to the buoy for the convenience of being taken without lighters. The other pair is laid down near the edge of the reef, one of the anchors being among the rocks, thereby leaving the best of the anchorage unoccupied.

At the inner mooring, in case of necessity, one vessel might be hove down by means of another.

About half a mile inland from South-west Bay, and behind the lava currents, lying near the beach, there is a tract of land of comparatively smooth surface, and of considerable dimensions; the soil is very rich, but so dry and dusty as seldom to exhibit any other verdure than a little purslane. A little further to the south-eastward, and behind some high conical hills there is a sandy plain having an area of, perhaps, twenty or thirty acres. This level is surrounded by the above mentioned conical hills on the north, and on every other side by high ridges of lava, through which the rains have worn finmari, or water courses, by which considerable quantities of sand and pummice have been discharged into the plain. I could trace very distinctly a line of pummice and other floating materials on the foot of the hills along the

An interesting account of these rollers will be found in the Voyage of H.M.S. Chanticleer, Capt. Foster, by Mr. Webster, her surgeon, who attributes them to the weak south-east trade being unable to keep the surface water of the ocean from flowing down from the northward, and being interrupted by the islands, washing up their beaches.-ED.

lee side of the plain, left as the last high-water mark, and shewing most clearly that at times there has been a depth of several feet of fresh water in the valley, a quantity sufficient to supply the island for many years. This affords the strongest proof of the occasional heavy rains that must fall at Ascension, and points out the propriety of constructing tanks in eligible situations.

The principal supply of fresh water is obtained on the Green Mountain, where there are several drips of water, which yield from 500 to 1,500 gallons daily, according to the wetness of the season. The rain falling on the mountain is absorbed by the porous and light soil, and descends by its gravity till it meets with a thin stratum of pummice dust, which, in the course of time has been in a manner petrified: this arrests the water in its progress downwards, and being generally inclined to the horizon, the water glides along and appears on the surface of a cliff in the shape of a spring. It is to be regretted that the strata above mentioned are faulty in so many places that much water passes through the rents, and is lost in the soil below.

There are two very good stone tanks built in the mountain, in contact with and parallel to rocky cliffs. The surface of the rock has been cleaned and gutters cut, by which meaus all the water that is not absolutely absorbed during rains, on a very considerable surface, must run into tanks. The tanks in the mountain are to be connected with others below, near the landing place at Tartar Stairs, by means of cast iron pipes, the distance between them being five miles.

There are at present tanks of solid masonry, capable of containing 2,400 tons of water, so that the time is not far distant when a ship may obtain a supply of water, vegetables, fruit, fish, and turtle, together with good and wholesome provisions, for the air is so dry and pure that no condemnation of provisions has yet taken place, a circumstance highly favourable for the island as a victualling depôt; and if we estimate the value of her anchorage by the degree of security afforded to shipping, then, that of Ascension will be one of the very best, for here the constant south-east wind blows in a moderate breeze. There is neither calm, gale, squall, nor change of wind; so that a ship might lie at single anchor with half cable for any length of time, in perfect safety.

WILLIAM WALKER.

Queen's Harbour-Master, Plymouth.

THE VARIATION OF THE COMPASS.

Royal Observatory, August 28th, 1841, Magnetical and Meteorological Department,

Mean Magnetic Variation for July 1841—23° 15′ 34′′.

THE SKERRIES Light.

Ir will be remembered that, in December last, an action was brought in the Court of Queen's Bench, Dublin, by Messrs. Richardson and Boyce, against the proprietors of the Skerries light-house, for trespass. The latter having seized the steamer Mercury, the property of the plaintiffs, for the non-payment of dues which it was alleged had been incurred by that vessel on a voyage from Cork to Dublin. The plaintiffs obtained a verdict; and we refer to the case because, in the course of the trial, it was clearly shown that under the royal grant which empowered the levy of one penny per ton on shipping by the owners of the Skerries, a large revenue was produced, which was every year augmented; and that it was highly necessary that commerce should be relieved of the tax. The Trinity Board, taking this view of the matter, have since (acting upon the authority given them by an Act of Parliament,) called upon the owners of the Skerries to transfer their right to the corporation; and, as might have been anticipated, a question arose about the value of the rock, light, and revenue, so to be transferred. To decide this question a precept was issued by the High Sheriff of Anglesey, and a special jury was empannelled on the 26th instant, when the property was assessed at 444,000l., this sum being estimated as twenty years' purchase.

This is purchasing the destruction of an imposition at a very heavy rate; but heavy as it is, we had rather, even at this price, have the purchase made now, than suffer such a property to remain longer in the hands of irresponsible possessors, without hope of a reduction in the charges levied on shipping.

The value fixed, by the verdict of the jury, on the Skerries light-house, may be referred to hereafter as a positive lesson on the evils of procrastination in matters which concern commerce; and it is an example of the injustice of granting, without the protection of ample provisionary considerations, the right to private persons to exact toll or tax for anything contrived, and necessary for the public convenience. The Skerries light was erected in the reign of Queen Anne, 1713, by one William Trench, who received a patent for sixty years, which enabled him to collect one penny per ton from certain vessels. This right was made perpetual, seventeen years after, by George the II., a monarch dear to memory, as the introducer of the excise system of taxation, and other grievous impositions; but neither the king nor his minister, Walpole, could by any possibility have contemplated that the profits to be derived from the grant, would ever have increased to the vast sum they at present amount to. It was proved, that during the last year 20,000l. was received as light dues for the Skerries-this led to the verdict. Eight years ago, the value would have been adjudged, by the very same process, at something more than half the sum; the net annual revenue arising out of the Skerries, taking the average of seven years ending 1833, being 12,524l. 158. 2d.

At the end of the last war, when trade began to increase, and merchant ships to multiply, the Trinity Company should have acquired possession of all private lights; and the trick of granting patents to the projectors of new ones should have ceased. But the Brotherhood of that day had no forethought; they did not possess the intelligence and energy that an efficient discharge of their important duties required of them; there are few of these left now; and it will be for the corporation itself, and for the shipping interest especially, if at future Trinity elections those candidates are always rejected who are described in the Nautical Magazine as "Dead-reckoning,-this-here-buoy men,"-and whom we consider as the ordinary seamen of the establishment; for we are persuaded that all the good that has lately, or may be hereafter achieved, will, as it has, originate and be accomplished by the superior officers connected with the corporation, who alone save it from falling into impotence and ridicule. A naval and an East India officer delivered a judgment in a case the other day in the Admiralty Court, as Trinity masters, which the fraternity may refer to, and be gratified in exhibiting so good a proof that there are some sailors amongst them;