they drank several glasses, and thought it nothing inferior to spring water. He made them a bowl of punch of it, which was highly commended.

He had not the convenience of a still, or he should have repeated the experiment for the conviction of some of his friends: for as to himself, he was firmly persuaded, that wood ashes mixed with sea-water would yield, when distilled, as good fresh water as could be wished for. And he thought, if every ship bound a long voyage was to take a small still with Dr. Hales's improvements, they need never want fresh water. Wood-ashes might easily be made, while there was any wood in the ship, and the extraordinary expense of fuel would be trifling, if they contrived so that the still should stand on the fire along with the ship's boiler.

All sweet or pure water, if preserved in wood, will soon dissolve a part of its interior surface, and become corrupt. To avoid this Mr. Bentham proposed the following plan, for which he received a gold medal from the Society of Arts. "The mode," says he, "in which I conceived fresh water might be preserved sweet, was merely by keeping it in vessels of which the interior lining at least should be of such a substance as should not be acted upon by the water, so as to become a cause of contamination. Accordingly, on-board two ships, the greater part of the water was kept, not in casks but in cases or tanks, which, though they were made of wood, on account of strength, were lined with metallic plates, of the kind manufac tured by Mr. Charles Wyatt, of Bridge-street, under the denomi nation of tinned copper-sheets; and the junctures of the plates or sheets were soldered together, so that the tightness of the cases depended entirely on the lining, the water having no where access to the wood. The shape of these cases was adapted to that of the hold of the ship, some of them being made to fit close under the platform, by which means the quantity of water stowed was consi derably greater than could have been stowed, in the same space, by means of casks; and thereby the stowage-room on-board ship, was very much increased.

The quantity of water kept in this manner on-board each ship, was about forty tons divided into sixteen tanks; and there was likewise, on-board each of the ships, about thirty tons stowed in casks as usual,

As the stowing the water in tanks was considered as an experiment, the water in the casks was used in preference; that in the tanks being reserved for occasions of necessity, excepting that a small quantity of it was used occasionally for the purpose of ascer taining its purity, or when the water in the casks was deemed, when compared with that in tanks, too bad for use.

The water in thirteen of the tanks, on-board one ship, and in all the tanks on-board the other, was always as sweet as when first taken from the source; but in the other three of the tanks, on-board one ship, the water was found to be more or less tainted as in the casks. This difference, however, is easily accounted for, by sup posing that the water of these tanks was contaminated before it was put into them; for in fact the whole of the water was brought on-board in casks, for the purpose of filling the tanks, and no particular care was taken, to taste the water at the time of taking it on board

After the water kept in this manner had remained on-board a length of time which was deemed sufficient for experiment, it was used out, and the tanks were replenished as occasion required: but in some of the tanks, on-board one ship at least, the original water had remained three years and a half. About twenty-five gallons of the water, which had remained this length of time in the ship, were sent to the Society, in two vessels made of the same sort of tinned copper with which the tanks were lined.

A certificate from Captain William Bolton, commander of the said vessel, dated Sheerness, 28th of June, 1800, accompanied this letter, stating that the water delivered to the Society was taken from a tank holding about seven hundred gallons, and which his predecessor, Captain Portlock, had informed him had been poured into the tank in December 1796, except about thirty gallons added in 1798, and had remained good during the whole time.

In a letter, dated January 7, General Bentham also states, that the water which had been preserved sweet on-board his Majesty's sloops Arrow and Dart, was taken from the well at the king's brew. house, at Weevil, from whence ships of war, lying at or near Portsmouth, are usually supplied with water for their sea-store, as well as for pressent use."

EDITOR,

ON EMBANKMENTS, PIERS, HARBOURS, &c. $75

SECTION XII.

On Embankments, Piers, Harbours, and gaining Land from the Sea.

IN various sections of the present chapter, and particularly that on Inundations, we have seen the dry land occasionally encroached upon to a very considerable extent by the natural action of different seas or rivers. In other instances, and particularly in the section of a preceding chapter, which treats of the formation of new islands, we have seen the dry land make similar encroachments upon the surrounding beds of water. "In this manner the boundaries of organized life are alternately extending and diminishing; in the former instance sometimes thrown up all of a sudden by the dread agency of volcanoes, and sometimes reared imperceptibly by the busy agency of corals and madrepores. Liverworts and mosses first cover the bare and rugged surface, when not a vegetable or any other kind is capable of subsisting there, they flourish, bear fruit, and decay; and the mould they produce forms an appropriate bed for the higher order of plant-seeds which are floating in the breeze or swimming on the deep. Birds next alight on the new formed rock, and sow with interest the seeds of the berries, or the eggs of the worms and insects on which they had fed, and which pass through them without injury. Thus the vegetable mould becomes enriched with animal materials; and the whole surface is progressively covered with herbage, shaded by forest trees, and rendered a proper habitation for man and the domestic animals that attend upon him.

"The tide that makes a desolating inroad on one side of a coast throws up vast masses of sand on the opposite. The lygeum or sea-mat weed, that will grow on no other soil, thrives here and fixes it, and prevents it from being washed back or blown away. Thus fresh lands are formed, fresh banks upraised, and the boisterous sea repelled by its own agency, and there are a variety of other plants whose roots or ramifications have an equal tendency to fix the quicksand, and produce the same effect: such, especially, as the

elymus arenarius, arundo arenarius, triticum repens, and several species of the willow *.”

Mr. Anthony Tatlow, probably copying some previous experi ments of Sir Thomas Hyde Page, Bart. has ingeniously employed the common furze for the same purpose; and by forming it into an extensive hedge, has made the sea produce a valuable and regular embankment of its own sand. His account of this ingenious contrivance, as communicated to the Board of Agriculture, A. D. 1800, is as follows:

"The embankment against the sea, that I mentioned when last at the Museum, is upon the estate of the Earl of Ashburnham, at Pembrey, in the county of Carmarthen, whither his lordship sent me upon his coal and other business, and with directions to see if I could devise any method of preventing the sea from making further incroachment upon his property, which it had been doing for many years, and particularly in October 1795, had broke in and covered many hundred acres, damaged the houses, buildings, stack-yards, and gardens; and it was the general opinion, that a regular embankment must be formed, which would cost some thousand pounds, he having several miles of coast. The view that I first took was upon a very windy day, and the shore an entire sand, which extended at low water many miles. In riding along, I perceived that any piece of wood, or accidental impediment to the course of the sand, raised a hill: it immediately occurred to me, that by making a hedge at the weak and low places, with wings to catch the sand as the wind blew it in different directions, I should obtain the desired effect. I therefore directed stakes nine feet long to be cut, and drove one foot and a half into the sand, at two feet and half distance from each other; betwixt which I had furze interwove, so as to form a regular furze hedge seven feet and a half high. Of this, since last June, I have done eleven hundred and thirty-seven yards; and in October last when I was there, a great deal of the hedge was covered, and since that time I am informed by letter, that a great deal more of it is so; and that the neighbouring inhabitants draw great comfort to themselves, from the security my furze embankment

* We are indebted for these remarks to the use of an unpublished Work of a literary friend, well known to the world. EDITOR

gives them, as its present appearance plainly evinces, that at a trifling expense I can secure Lord Ashburnham's estate from being inundated; for, whenever the first hedge is not high enough to prevent the sea overflowing, another may be built upon the sand formed by that hedge, and so on in succession, till it is perfectly safe."

Similar means have not only been employed to prevent encroachments from the sea; but in various instances to gain land from it. It often happens, however, that the machinery must here be somewhat more complex, and intersected with drains and sluices. One of the simplest schemes of this kind which we have lately met with is the following by the Rev. Bate Dudley, which we shall copy in his own words, as communicated to the Society for the Encouragement of Arts, Manufactures and Commerce, and for which he received the gold medal.

"A tract of land, which I inclosed on the same line of coast within this parish about eleven years ago (for which I was then honoured with the Society's gold medal) being already under a profitable course of tillage, I was induced to undertake the present inclosure, as a lessee of the collegiate estate of St. Paul's. The front line of embankment against the sea is nearly one mile in length, and, with the returning banks on each wing to the old wall, forms an inclosure of contents, as expressed in the certificate already in your possession. The whole of the embankment is composed of earth alone, borrowed from the irregular salting land in the front, called chatts, and taken at the limited distance of twelve feet from the base of the new work, to leave a sufficient foreland for its protection. I found, from experience, in my former embankment, that I had not given it a sufficient angular declension in front, for an easy ascent and descent of the waves. This error was therefore corrected in the last work. I began it on a base of thirty-two feet, and wrought it to the height of seven feet, leaving it a plane of five feet on the top, and making the land-side of the embankment, as nearly perpendicular as the security of the base would allow.

"Within, on the land-side, is cut a ditch, twelve feet wide, five feet deep, and four feet at bottom; the earth from which was thrown into the mound. My former sea.embankment, in Bradwell parish, had nearly given way to the great inundating tide of February 1792, from this erection of new earth being made on the surface. To guard against similar danger in the present work, a