person with a low flat nose, hollowed in the middle.

The Tartars are great admirers of camus beauties. Rubruquis observes, that the wife of the great Jenghis Kan, a celebrated beauty, had only two holes for a nose.

Can, in the sea-language, as can-pump, a vessel, wherein seamen pour water into the pump to make it go.

Can-buoy, a larger size of buoy, used to discover dangerous... But as the lower gate is strained in proportion to the depth of water it supports, when the perpendicular height of the water exceeds 12 or 13 feet, more locks than one become necessary. Thus, if the fall be 17 feet, two locks are required, each having $8\frac{1}{2}$ feet fall; and if the fall be 26 feet, three locks are necessary, each having 8 feet 8 inches fall. The side-walls of a lock ought to be very strong. Where the natural foundation is bad, they should be founded on piles and platforms of wood: They should likewise flop outwards, in order to resist the pressure of the earth from behind.

Plate LX. fig. 1. A perspective view of part of a canal: the vessel L, within the lock A C.—Fig. 2. Section of an open lock: the vessel L about to enter.—Fig. 3. Section of a lock full of water: the vessel L raised to a level with the water in the superior canal.—Fig. 4. Ground section of a lock. L, a vessel in the inferior canal. C, the under gate. A, the upper gate. G H, a subterraneous passage for letting water from the superior canal run into the lock. K F, a subterraneous passage for water from the lock, to the inferior canal.

X and Y (fig. 1.) are the two flood-gates, each of which consists of two leaves, resting upon one another, so as to form an obtuse angle, in order better to resist the pressure of the water. The first (X) prevents the water of the superior canal from falling into the lock; and the second (Y) dams up and sustains the water in the lock. These flood-gates ought to be very strong, and to turn freely upon their hinges. In order to make them open and shut with ease, each leaf is furnished with a long lever A b, A b; C b, C b. They should be made very tight and close, that as little water as possible may be lost.

By the subterraneous passage G H (fig. 2, 3, &c.) which descends obliquely, by opening the sluice G, the water is let down from the superior canal D, into the lock, where it is kept and retained by the gate C when shut, till the water in the lock comes to be on a level with the water in the superior canal D; as represented, fig. 3. When, on the other hand, the water contained by the lock is to be let out, the passage G H must be shut by letting down the sluice G, the gate A must be also shut, and the passage K F opened by raising the sluice K: A free passage being thus given to the water, it descends through K F, into the inferior canal, until the water in the lock is on a level with the water in the inferior canal B; as represented, fig. 2.

Now, let it be required to raise the vessel L (fig. 2.) from the inferior canal B, to the superior one D; if the lock happens to be full of water, the sluice G must be shut, and also the gate A, and the sluice K opened, so that the water in the lock may run out till it is on a level with the water in the inferior canal B. When the water in the lock comes to be on a level with the water at B, the leaves of the gate C are opened by the levers C b, which is easily performed, the water on each side of the gate being in equilibrium; the vessel then falls into the lock. After this the gate C, and the sluice fluece K are shut, and the fluece G opened, in order to fill the lock, till the water in the lock, and consequently the vessel be upon a level with the water in the superior canal D; as is represented in fig. 3. The gate A is then opened, and the vessel passes into the canal D.

Again, let it be required to make a vessel descend from the canal D, into the inferior canal B. If the lock is empty, as in fig. 2, the gate C and fluece K must be shut, and the upper fluece G opened, so that the water in the lock may rise to a level with the water in the upper canal D. Then open the gate A, and let the vessel pass through into the lock. Shut the gate A and the fluece G; then open the fluece K, till the water in the lock be on a level with the water in the inferior canal; then the gate C is opened, and the vessel passes along into the canal B, as was required.

It is almost needless to spend time in enumerating the many advantages which necessarily result from artificial navigations. Their utility is now so apparent, that most nations in Europe give the highest encouragement to undertakings of this kind wherever they are practicable. The advantages of navigable canals did not escape the observation of the ancients. From the most early accounts of society we read of attempts to cut through large isthmuses, in order to make a communication by water, either betwixt different nations, or distant parts of the same nation, where land-carriage was long and expensive. Herodotus relates, that the Cnidians, a people of Caria in Asia Minor, designed to cut the Isthmus which joins that Peninsula to the continent; but were superstitious enough to give up the undertaking, because they were interdicted by an oracle. Several kings of Egypt attempted to join the Red-sea to the Mediterranean. Cleopatra was exceedingly fond of this project. Suleiman II., emperor of the Turks, employed 50,000 men in this great work. This canal was completed under the caliphate of Omar, but was afterwards allowed to fall into disrepair; so that it is now difficult to discover any traces of it. Both the Greeks and Romans intended to make a canal across the Isthmus of Corinth, which joins the Morea and Achaia, in order to make a navigable passage by the Ionian sea into the Archipelago. Demetrius, Julius Caesar, Caligula, and Nero, made several unsuccessful efforts to open this passage. But, as the ancients were entirely ignorant of the use of water-locks, their whole attention was employed in making level cuts, which is probably the principal reason why they so often failed in their attempts. Charlemagne formed a design of joining the Rhine and the Danube, in order to make a communication between the ocean and the Black-sea, by a canal from the river Almutz which discharges itself into the Danube, to the Reditz, which falls into the Maine, and this last falls into the Rhine near Mayence: For this purpose he employed a prodigious number of workmen; but he met with so many obstacles from different quarters, that he was obliged to give up the attempt.

The French at present have many fine canals: That of Briare was begun under Henry IV. and finished under the direction of cardinal Richelieu in the reign of Lewis XIII. This canal makes a communication betwixt the Loire and the Seine by the river Loing. It extends eleven French leagues from Briare to Montargis. It enters the Loire a little above Briare, and terminates in the Loing at Cepci. There are forty-two locks on this canal.

The canal of Orleans, for making another communication between the Seine and the Loire, was begun in 1675, and finished by Philip of Orleans, regent of France, during the minority of Lewis XV. and is furnished with twenty locks. It goes by the name of the canal of Orleans; but it begins at the village of Combleux, which is a small French league from the town of Orleans.

But the greatest and most useful work of this kind is the junction of the ocean with the Mediterranean by the canal of Languedoc. It was proposed in the reigns of Francis I., Henry IV., and was undertaken and finished under Lewis XIV. It begins with a large reservoir 4000 paces in circumference, and 24 feet deep, which receives many springs from the mountain Noire. This canal is about 64 leagues in length, is supplied by a number of rivulets, and is furnished with 104 locks, of about eight feet rise each. In some places it passes over bridges of vast height; and in others it cuts through solid rocks for 1000 paces. At one end it joins the river Garonne near Thoulouse, and terminates at the other in the lake Tau, which extends to the port of Cete. It was planned by Francis Riquet in the 1666, and finished before his death, which happened in the 1680.

In the Dutch, Austrian, and French Netherlands, there is a very great number of canals; that from Bruges to Oostend carries vessels of 200 tons.

The Chinese have also a great number of canals; that which runs from Canton to Pekin, extends about 825 miles in length, and was executed about 800 years ago.

It would be an endless task to describe the numberless canals in Holland, Russia, Germany, &c. We shall therefore confine ourselves to those that are either already finished, or at present executing in our own country.

As the promoting of commerce is the principal intention of making canals, it is natural to expect that their frequency in any nation should bear some proportion to the trade carried on in it, providing the situation of the country will admit of them. The present state of England and Scotland confirms this observation. Though the Romans made a canal between the Nyne, a little below Peterborough, and the Witham, three miles below Lincoln, which is now almost entirely filled up, yet it is not long since canals were revived in England. They are now however become very numerous, particularly in the counties of York, Lincoln, and Cheshire. Most of the counties betwixt the mouth of the Thames and the Bristol channel are connected together either by natural or artificial navigations; those upon the Thames and its reaching within about twenty miles of those upon the Severn. The duke of Bridgewater's canal in Cheshire runs twenty-seven miles on a perfect level; but at Barton it is carried by a very high aqueduct bridge over the Irwell, a navigable river; so that it is common for vessels to be passing at the same time both under and above the bridge. bridge. It is likewise cut some miles into the hills, where the Duke's coal mines are wrought.

Though a navigable communication between the rivers Forth and Clyde in Scotland had been long talked of, it was never considered with a view to execution till the year 1761, when the ground was surveyed by Mr Smeaton, at the desire of the trustees for fisheries and manufactures in Scotland. From Mr Smeaton's survey and report, the practicability of this canal was fully demonstrated. But, after the scheme became an object of general attention, it was found that a canal of larger dimensions than the one originally proposed would be productive of still greater advantages to the nation. Mr Smeaton was therefore directed to make a second survey, and to report to the intended proprietors an estimate of the expense of making a canal 24 feet broad at bottom, 54 at top, containing seven feet deep of water, and extending from the Forth to the Clyde, a distance of about 31 miles, with a collateral branch to the town of Glasgow, which is about six miles, and another from Bainsford to the river Carron below Carron-works, making in all about 37 miles. This report was approved of, an act of parliament was obtained, and the canal is now cutting upon this very plan. It begins at the Holemerrie in the mouth of the Carron, and terminates at Dumbuir-burn-foot on the river Clyde, about seven miles below Glasgow. Above seven miles are already cut, from the Holemerrie westward; a number of hands are likewise employed at the point of partition in Dollater-bog, and the whole is expected to be finished in five years. At the point of partition, which is 168 feet above the level of the sea at low water, a very large reservoir is to be made for supplying the canal; and the vessels are to be raised and lowered by means of 41 locks. Where the course of the canal is intersected by burns or rivers, it is to be carried over them by aqueduct bridges; three of these bridges will be large, and require considerable labour and expense, viz. one over the Grangeburn, one over Bony-mill-burn, and a third over the Kelvin in the Glasgow branch. The expense of executing the whole is computed to be about 150,000l.

Sea-vessels, about 20 feet wide and 60 feet long, and carrying 70 or 80 tons, may pass along by this canal from the one frith to the other. But it will admit a free passage to vessels of 140 tons, provided they be built in the manner of the flat vessels used by the Dutch. The toll-duty, allowed by the act of parliament, is not to exceed 2d. a ton per mile. Privileged goods, such as lime and lime-stone, are to pay only one third of the usual toll-duty; stones, gravel, and other materials for making or repairing roads, likewise dung, soil, marle, and all sorts of manure, are exempted from paying any toll-duty, provided they do not pass any lock but when the water shall flow over the place made for discharging the overplus-water in the canal.

We must not conclude this article without observing, that in Ireland also the utility of artificial navigations has not been unattended to. Several canals are there making; in particular, one from Loch Neach to Newry, about 20 miles; and another from the river Shannon to Dublin, about 70 miles.