avoid the shoal; or approach the light not nearer than 2 miles an East bearing. The southern point of this shoal lies S.E. S., 24 miles, and the northern point N.N.E., three-quarters of a mile, from the lighthouse.

Immediately round the north end of the cape a breakwater has lately been constructed, to the westward of which there is another pile of masonry, named the Ice Breaker, which has been built for the purpose of protecting the anchorage within the breakwater from the ice, which at certain periods of the year comes down the river in large quantities. On the west end of the prin cipal breakwater is a lighthouse, showing a small fixed light at 56 feet, visible about 12 miles.

To run into the anchorage between the breakwater and the shore, from the southward, pass the Hen and Chicken Shoal at the distance of about 2 miles from the shore, then haul in close to the shore, keeping as close as convenient to Cape Henlopen, as it is steep-to, there being from 9 to 10 fathoms immediately off it; thence you may steer to the anchorage. If from the eastward, bring Cape Henlopen Lighthouse to bear W. by S., and stand in. The harbour may be entered at either end, or between the Breakwater and Ice Breaker, according to the wind and tide, and to the berth selected. Do not anchor in the Gat. The best anchorage is close to the main-work, with the Breakwater Lighthouse bearing N. by W. The holding-ground is good in every part of the harbour, and there is no difficulty in running for it in a gale of wind.

Within the river there are numerous banks, which are in general buoyed; and the course up the river is well lighted, both by floating-lights and lights on the shores. In consequence of the intricacy of the navigation it would be imprudent to attempt the river without a pilot.

RIVER CHESAPEAKE.-From the River Delaware the coast runs to the S.S.W. about 110 miles, to Cape Charles, at the entrance of the Chesapeake, and is in general sandy and marshy. There are various dangerous shoals off the shore, namely, the Fenwick's Island Shoal, Gull Banks, Sinepuxent Shoals, &c., so that it is recommended to keep as far off the land as possible, particularly as it is low, and in consequence difficult to recognise. On the southern end of Assateague Island is a lighthouse bearing a fixed light, and there is also a lighthouse on Smith's Island, near Cape Charles, which shows a revolving light.

In sailing along the coast of Deleware and Maryland in the vicinity of Rehoboth Bay and Sinepuxent Sound you will have 5 to 8 fathoms, at the distance of about 3 miles from the coast, and a strong current setting to the southward; but it is recommended to keep at a much greater distance off on account of the shoals previously mentioned, which lie more or less at a distance of 7 to 8 miles from the land. The harbour of Chincoteague is in about latitude 37° 55′ N., and is occasionally run for by small coasting ves sels, in cases of great emergency; but it is said to require considerable care when going in. There is also Matomkin Harbour, also used by coasters. When you are to the southward of Chincoteague, steer to the S.S.W. for the lighthouse on Cape Henry, keeping the lead going, because that the northern part of the Machapungo Shoals, lies 4 or 5 leagues to the northward of Smith's Island, and the southern part of them comes nearly abreast of the said island. As you approach Smith's Island you will have 13 fathoms, and in some places but 3 or 4 fathoms, on a bottom shoaling gradually to the shore. In lat. 37° 30', and in long. 75°, you will have from 26 to 27 fathoms, which will be about 35 miles from the land. Along this coast is a strong current running to the S.S.W., in the direction of the shore, at the rate of from 2 to 24 knots an hour.

From the Capes of Virginia, or the Chesapeake, the shore is generally steep, as far as the Wimble Shoals, to the southward, which lie in lat. 35° 32', at about 7 miles off shore. The greatest extent of soundings from shore is to the eastward of Cape Henry; it being, in that part, between 23 and 24 leagues, with various depths. At the distance of about 7 leagues, and in the latitude of the cape, there is a bank of 94 fathoms, between which and the cape there are 11 and 12 fathoms, and there is the same depth to some distance without it. The bank is of small extent, and there are 14 and 16 fathoms north and south of it. To the eastward the water deepens gradually to 25 fathoms; it then suddenly shoalens to 20, and, again, in like manner, suddenly deepens to the edge of soundings. The ground off Cape Henry is in general coarse sand, with some gravel; but thence to Cape Hatteras it is commonly fine sand, with oaze.

Ships falling in with the land to the northward of the entrance, should not stand inwards to a less depth than 7 fathoms, until they come into the latitude of Smith's Island and Cape Charles, whence they may stand with safety into 5 fathoms. In coming along shore from the southward, 7 fathoms will be a proper depth to keep in, until up with Cape Henry; whence falling into 8 or 9 fathoms, with sticky bottom, you will be in the channel-way. When you come in towards the land, to the southward of Cape Henry, you will have deeper water than when you are in the latitude thereof, as 21 fathoms, reddish sand, and pretty large: 9 leagues off it there are 35 and 40 fathoms, fine grey sand.

The land is low and sandy; you cannot see it above 7 leagues off. Cape Henry is low, but bluff, with a few trees to the sea side, at a little distance from the water; it is moderately steep-to, excepting that a small shoal stretches about 2 cables' length from the shore east of the lighthouse, and there is nothing to hinder a ship from passing into Lynhaven Bay, where there is soft ground, and from 4 to 6 fathoms water. The bank, named the Middle Ground, is about 4 miles from the cape.

When coming in from sea, in the latitude of Cape Henry, you will meet with soundings as above described. You may readily ascertain when in soundings by the muddy colour of the water. In clear weather the land of Cape Henry may be seen from the depth of 10 or 11 fathoms, regular soundings, which lie 5 or 6 leagues to the southward of the cape; more to the northward, the soundings are irregular and coarser, as above described.

The Middle Ground off Cape Henry now extends more to the soutward than formerly; and it is said that there are 4 fathoms, with the lighthouse bearing W. by S., 5 miles. This bearing, therefore, now leads over the tail of the bank; and the safest course in is with the lighthouse W.N.W., or W. by N.

Chesapeake Bay is 160 miles in extent from North to South, and is considered to be one of the finest estuaries in the globe. It is the recipient of many rivers which fall into it on all sides, as the Susquehanna, Patapsco, Patuxent, Potomac, &c.

In advancing towards the entrance of the Chesapeake, the Gulf Stream is usually crossed from the south-eastward, in its narrowest part, near the parallel of Cape Hatteras, or 35° 10′ N. In crossing it thus, the temperature of the water will be found, in September, to be about 83°, thence diminishing to the shore. Even in December, when in soundings of 19 fathoms in latitude 35° 19', with the air at 45°, the water has been found at 68°, after getting into soundings. Within the stream, after reaching soundings, you will get into the cold southerly current, the prolongation of the currents passing over the Newfoundland Banks.

The lighthouse on Cape Henry, in latitude 36° 56', is an excellent mark for the Chesapeake; it shows a fixed light at 120 feet above the sea, visible 24 miles. Having passed the cape, in sailing upward, in the main stream, low banks, fringed with trees, are all that is to be seen of the country, excepting here and there a house near the shore, and occasionally a lighthouse, small town, or village.

It should be observed, generally, that in the Chesapeake, all the low points, both of Virginia and Maryland, have shoals extending from them; and should, therefore, have a good berth in passing, the water being shoal.

To run up the Chesapeake a pilot is always taken by strangers.

CHARLESTON HARBOUR.-Between the Chesapeake and Charleston there are no harbours of any importance, which are visited by large foreign vessels. In coasting along it will be necessary to give a wide berth to Capes Hatteras, Lookout, and Fear, as from them shoals run out to seaward, from 10 to 15 miles, and are the more dangerous, as their outer edges are steep-to. The coast about Cape Roman has also sandy flats off it, extending out 6 or 7 miles from the land, which must not be approached nearer than 7 fathoms. The shore is very low throughout the whole of this extent of coast, and affords but few objects easily recognized at sea.

The lighthouse at the entrance of Charleston Harbour bears S.W. ↓ W., 31 miles, from that of Cape Roman; between are several low islands, the principal of which are named Bull's, Cooper's, Davies', Long, and Sullivan's Islands. Flats extend from all the islands, along which the soundings are regular. Bull's Island appears very bluff, with red sand-hills, and a spit from the outer end of it extends eastward, about 34 miles; a spit named the Rattle-snake, also extends to the distance of 3 miles, E. by S., from Sullivan's Island, which forms the north side of the entrance to Charleston, and you will be on the edge of it in 5 fathoms. With Charleston Churches to the northward of Sullivan's Island, you will be on the edge of the Rattlesnake; and when the churches are open to the southward of Sullivan's Island, you are clear of that shoal. You should approach no nearer to this bank than in 5 fathoms water.

The entrance to Charleston Harbour is distinguished by a lighthouse erected on a low sandy point upon Morris's or Lighthouse Island; the lantern is 125 feet above the sea, and exhibits a revolving light, which may be seen 8 or 9 leagues off. When drawing nigh it, the time of darkness will be twice that of illumination, and, as you approach, the period of darkness will decrease, and that of light increase, until you get within the distance of 3 leagues, when the light will never wholly disappear; but the greatest strength of the light, in comparison with the least, will be as 24 to I. St. Michael's Church, at Charleston, is also an excellent mark, it having been painted pure white: it may be seen in clear weather nearly 7 leagues. There is also a small beacon on the same island, which is lighted.

Off Charleston Bar there is good anchorage in 6 fathoms, with the lighthouse W. by N., 6 miles, and Sullivan's Island N.W. W., 7 miles.

Channels and their Buoys.-There are two white beacons on Morris's Island, which, when kept in range, will bring you to a buoy lying at the entrance of the Overall Channel; and by keeping the beacons directly on with each other, and steering for them until you strike 5 fathoms water, you may then direct your course to Sullivan's Island.

There are three buoys in the North Channel, which serve to direct you by running for the outer buoy, and leaving it on the port hand, thereafter for the middle buoy which you leave on your starboard hand, and then for the inner buoy which you leave on the port hand. The same water may

nearly be found in this as in the Overall Channel, but the latter is to be preferred.

There is one buoy at the entrance of the Lawford Channel, which may be found by keeping the South Beacon (which is not lighted) open to the northward of the lighthouse about three handspikes' length. Leave the buoy on the starboard hand at the distance of 50 yards, and steer N.N.E. to clear shoals on the port hand, until the lighthouse bears W.N.W., when you should direct your course to Sullivan's Island.

The Ship Channel and Bar lie between the north and south breakers, which will be seen as you approach. When standing in for the bar, you should bring the beacon on Lighthouse Island to appear a handspike's length to the north of the lighthouse, and you will soon make the Bar Buoy, lying in 3 fathoms water, and which may be passed on either side. Nearly in the same range lie two other buoys; the first on the south point of the north breaker, and the other on the inner south point (or S.W. point) of the same breaker. These buoys are to be left on the starboard hand, at the distance of a ship's length. After passing the inner buoy, steer North or N. W. (according as the tide is flood or ebb) for Sullivan's Island, keeping the two beacons on it in range until you are up with the buoy off Cummin's Point, which you leave on your port hand. The course from the buoy off Cummin's Point is N.W. by N. to the anchorage in Rebellion Roads. You will clear the Middle Ground, when mid-way between Sullivan's Island and the buoy off Cummin's Point, by steering for Fort Pinckney, keeping it a little on the port bow. As you approach the island yon must give it a berth of 100 yards, and anchor off the city.

TIDES. It is high water on the American coast at the various undermentioned places, as follows:

On the south side of the Gulf of St. Lawrence, 9 hours The tide rushes with much rapidity through the Gut of Canso, in the narrowest part of which it seldom runs at a slower rate than 4 or 5 miles an hour. On the south shore of Northumberland Strait the time of flowing on the full and change is from 7 to 8 hours; the perpendicular rise is from 3 to 7 or 8 feet. The tides here are very materially varied by the winds; it has been found that at times the stream of the Gut of Canso has continued to run one way for many successive days. It is high water at St. John's, Newfoundland, at 7h. 50m; the tides rise 6 to 8 feet, but very irregular, being much influenced by the winds. At Halifax dockyard it is high water on the full and change at 8 o'clock; springs rise from 6 to 9 feet. At St. John's, Newbrunswick, at 11h. 44m.; springs ise 24 feet. At Cumberland Basin at 12h.; springs rise 60 feet. At the eastern side of Manan Island at 10h; springs rise 25, neaps 20 feet. In Passamaquoddy Bay at 10h; springs 30, neaps 24 feet. At Annapolis Gut at 10h.; springs rise 18 feet.

The tides at the entrance, and within the Bay of Fundy, are very rapid but regular, and although the wind against them alters the direction of the ripplings, and sometimes makes them dangerous, yet it has little or no effect upon their courses. The flood tide sets from Cape Sable to the northwestward through the Seal, Mud, and Tusket Bald Islands, at the rate of 2 or 3 miles an hour, and in the channels among the islands it increases to 4 and 5 miles. From thence, taking the direction of the main land, it flows past Cape St. Mary, and then N.N.W. towards Bryer's Island; it runs up St. Mary's Bay but slowly, which adds to its strength along the eastern shore, then increasing its rapidity as the bay contracts, it rushes in a bore into the Basin of Mines and up Chignecto Bay, so that here the water sometimes rires to the extraordinary height of 75 feet.

It is high water off Boston Lighthouse at 10h.; it flows off the town till a quarter of an hour past 11; the springs rise 16 feet perpendicularly, neaps 12 feet. It is high water off Race Point, at 11h. 45m.; on leaving Cape Cod for Boston you must calculate the tide, as the flood sets strongly to the S.W. At Sandy Hook, at 7h. 29m., but the stream of tide continues to set in, at the rate of 2 knots, until 9h. At New York, East River, it is high water at 9h.; in the North, or Hudson's River, at 11 o'clock: the vertical rise of tide is about 7 feet, but it is sometimes checked by the westerly or north-westerly winds, so as to lower the water on the bar to 34 fathoms; easterly or north-easterly winds have frequently raised it to 5 fathoms. The flood sets strongly to the westward from the S.W. Spit, until above the Upper Middle, whence it runs up in the channel course to the Narrows.

In the Delaware it is high water, on the full and change of the moon, as follows:-Cape May, at 84h.; Cape James, or Henlopen, at 9h.; Bombay Hook, 10th.; Reedy Island, 11th.; Newcastle, 12h.; Philadelphia, 3 o'clock. First quarter flood sets near the capes W.N.W; second to last quarter N.N.W.; first quarter ebb E.S.E.; second to last quarter ebb S.S.E. With spring tides the vertical rise is from 6 to 7 feet; neap tides 44 to 5, but varied by the winds. The flood tide runs in round Cape Henry, and into Lynhaven Bay, until 11 o'clock, on the full and change, and out of the way of the Chesapeake stream it flows at 10h.; in Hampton Road, at 104h. The tide varies considerably in its direction, according to the time from ebb or flood. The ebb from James and York Rivers sets over the Middle Ground to the eastward, which renders the navigation thereabout dangerous in the night.

It is high water at Charleston at 7h. 15m. The depth of water on the bar at low water, neap tides, is 12 feet, at high water, neap tides, 17 feet; at low water. spring tides, 11 feet, high water, 18 feet. From thence towards Savannah, it has has been observed that N.E., E., and S.E. winds cause higher tides than other winds. At Port Royal the tide flows, in the full and change of the moon, at 8th. About 6 leagues from the land, in 12 fathoms water, the flood sets strongly to the southward, and the ebb to the northward; at a great distance from the shore there is no ebb at all. On Savannah Bar there are 20 feet, at low water. At St. Mary's River it is high water at 8th.; the tide rises 6 feet at common, and 7 feet at spring tides.

VARIATION.-The variation at St. John's, Newfoundland, is 28° W.; Cape Ray, 24; Quebec, 15°; St. Paul's Island, Gulf of St. Lawrence, 21°; Gut of Canso, 16; Halifax Lighthouse 13° 35'; Cape Sable, 11° 15'; Boston Bay, 7° 40′; in New York Harbour, about 7°; off the Delaware, 4°, and about the same off the Chesapeake.

SECTION VIII.

GENERAL DESCRIPTION OF WINDS, TIDES, CURRENTS, &c.

A change in the temperature of a portion of air, an increase or a diminution of the quantity of water, which it holds in a state of vapour; in short, any circumstance which causes it either to contract or to expand, destroys