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18

Distance and Tide Table for the Delaware River (Prepared by the United States Coast and Geodetic Survey)

This table gives, in first column, the distance of the following places from Washington Avenue Wharf, Philadelphia; in the second column the distances from place to place. The time of High Water at any place may be found by applying the correction found in third column to the time of High Water at Philadelphia for the date wanted.

(For time of High Water at Philadelphia, see page 16–17.)

Correction

nautical Nautical *ś. Miles. Miles. Add. – Signifies Subtract. h. m. Port Richmond Elevator, Philadelphia ........................ 3.30. 1.60– 15 - s off Fairmount Ave., Phila. ...... 1.70 0.25 + 12 Coopers Point, N.J. [...; 8. §. Phil. 1.45 0.65 Walnut St. Wharf, Philadelphia................................ 0.80 0.80+| || 06 Washington Ave. Wharf, Phila. (foot of Wash. Ave.)... 0.00 Kaighn's Point, N. J. (off Reed St., Philadelphia)...... 0.22 0.22— 02 Greenwich Point, Phila., (off lower R. R. dock)...... . 1.62| 1.40 09 League Island Navy Yard, (off center of dock).... . 4.52 2.90 22 Girard Point, Philadelphia................. ....... .............. 6.27 1.75– 24 Point Breeze Oil Works Schuylkill River (off upper | end of wharf)............................................ ....... 8.67 2.40— 15 Gibson's Point, Schuylkill River (off upper end of wharf 9.77 1.10— 12 Chestnut St. Wharf, Schuylkill River......................... 12.17 2.40 – 01 Opposite Essington, Pa. (on line with Dupont wharf).... 1050 —| 1 || 00 Chester, Pa. (Market St. Wharf)................................ 1330 2 so— 1 || 09 Schooner Ledge, Delaware River (between buoys)........ 15 10, 180 – 1 12 Marcus Hook, Pa., (off principal street)........ ............ 1830 3 20– 1 17 Cherry Island Flats (at junction of range, off Edgemoor) 24 10 580 – 1 || 43 Wilmington, Del., entrance to Christiana Creek ū. range with light).................... .......................... 25 90 180 – 1 39 Deep Water Point, N. J. (on line with W. & N. R. R. Wharf)............................................................. | 26.85 0.95–| 1 || 47 Newcastle, Del. (on line with Kelly's Point).... . 30.10 3.25— 1 54 Fort Delaware (wharf beam) ........ ............. ... 34.40. 4.30— 2 19 Reedy Island (off Tide Indicator).............................. 39.20, 4.80 – 2 43 Liston's Point (abeam).................. ... 45.00 5.80 – 3 24 Bombay Hook Light (abeam).................................... 48.25 3.25 – 3 || 33 Ship John Light (abeam).......... ... 54.90, 6.65—| 4 || 10 Cross Ledge Light (abeam)... ... 65.40 10.50 – 4 || 42 Maurice River Light (abeam)......... ... 68.70 3.30 – 4 41 Fourteen Foot Bank Light (abeam) ------------------- 72.50 3 80 – 4 54 Brandywine Shoal Light (abeam)......... ................ ... 77.30 4.80 – 5 11 Cape Henlopen (north end of Cape abeam).................. 88.00 10.70-I- 7 || 01 Overfalls Light Wessel............ ................. ... 89.10 1.10|-|-| 7 || 00 Five Fathom Bank Light Wessel .... ... 110.00. 20.90--| 6 || 06 Northeast End Light Wessel ...................................... 121.00, 11.00--| 6 || 15 From Washington Ave. Wharf, Phila., to Cape May, N. J. (Bay Shore Wharf) via Ricords Channel... 85.8 To Cape Henlopen (north end of Cape)................. 88.5 From Cape Henlopen to Cape May (Bay Shore Wharf) | via through Channel .......................... ............ 10.4 | COURSE DISTANCE From Overfalls Light Ship to Five Fathom Bank Light Ship... E. 34 S. 20.9 Nau. Miles From Five Fathom Bank Light Ship to N. E. End Light Ship. N. N. E. 33 E. 11.0 “ -AVERAGE DURATION AND HEIGHT OF TIDES, rosato, S Height. lse. (Ill. in We * h. m. h. m. ;" ź. 4;ge Philadelphia................................. 5.07 7.18 7.0 feet. 5.0 feet. 6.0 feet. New Castle.............. . 5.16 7.09 7.5 “ 54 “ 6.5 “ Delaware Breakwater................... 6.20 6.05 5.3 “ 3.4 “ 4.4 “

Compass Variation at Philadelphia, 79 Westerly.

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USE OF THE BAROMETER.

Commonly familiar as the practical use of the barometer as a weather-glass is at sea, as well as on land, only those who have long watched its indications and compared them carefully, are really able to conclude more than that a rising glass (column) usually foretells less wind or rain, a falling column (glass) more wind or rain, or both ; a high column fine weather, and a low one the reverse. But useful as are these general conclusions, in most cases, they are sometimes erroneous, and then depreciating remarks are rather hastily made, tending to discourage the inexperienced. By attending to the following brief observations (the results of many years' practice and persons' experience), any one not accustomed to use a barometer may do so with less hesitation and with immediate advantage : The column of mercury in a good barometer usually stands, on an average, some tenths of an inch higher, with or before polar and easterly winds, than it does with or before equatorial and westerly winds (of equal strength and dryness or moisture) in all parts of the oceans. (The terms polar and equatorial are used with reference to winds blowing from the nearest polar direction, or from the direction of the equator). This peculiarity causes many mistakes. The glass is high, perhaps, but falling. Wind or rain, or both, are expected in consequence, yet neither follow to any remarkable degree. A change of wind only from one quarter to another takes place. Reversely, the glass is low, but rising. Fine weather is expected; yet, instead of that, a strong wind, accompanied perhaps by rain, hail, or snow, rises from the polar direction. By such changes as these, seamen are often misled, and much calamity occurs sometimes. An impending fall of rain or snow affects the barometer, wind still more (having regard to the quarter whence it blows and the average difference). There may be heavy rains, or violent winds, beyond the horizon, and even the view of an observer, by which his instruments may be affected considerably, though no particular change of weather occurs in his immediate locality. Sometimes severe weather from an equatorial (southerly in north latitude,

northerly in the southern hemisphere) direction, not lasting long, may cause no.

great fall of the glass, because followed by a duration of wind from polar regions : and at times the column may fall considerably with polar winds and fine weather,

apparently against the rule (or law), because a continuance of equatorial winds is.

about to follow. There is little variation of the barometer between the tropics, because the wind blows generally in the same direction and with equal force, and no contending currents of air cause any considerable change in the temperature or density of the atmosphere. For great storms or hurricanes, however, within the tropics, the barometer falls very low, but soon returns to its usual state. It has been observed on some coasts that the barometer is differently affected by the wind, according as it blows from the sea or from the land, the mercury rising on the approach of the sea breeze, and falling previously to the setting in of the land wind. Some young seamen hardly appreciate sufficiently common rules about weather, which are as true as they are trite ; namely, that a red sky at sunset presages fine weather ; a red sky in the morning bad weather, or much wind, if not rain ; a gray sky in the morning, fine weather; that soft-looking or delicate clouds foretell fine weather, with moderate or light breezes; hard-edged, oily-looking clouds, wind ; that a dark, gloomy, blue sky is windy, but a light, bright blue sky indicates fine weather; that, generally, the softer the clouds look the less wind (but perhaps the

more rain) may be expected ; and the harder, more “greasy,” rolled, tufted, or

ragged, the stronger the wind will prove. Also that a bright yellow sky at sunset presages wind ; a pale yellow, wet ; and that by the preponderance of red, yellow or gray tints the coming weather may be foretold very nearly—indeed, if aided by instruments, almost accurately.

These indications of weather, afforded by colors, seem to deserve more critical.

study than has yet been given to the subject.

Why a rosy hue at suuset, or a gray, neutral tint at that time, should presage the reverse of their indications at sunrise ; why bright yellow should foretell wind at either time, and pale yellow, wet; why clouds seem soft, like water-color, or hard-edged, like oil paint, or Indian ink, or an oily plate, and why such appearances are infallible signs, are yet to be shown satisfactorily.

THE WEATHER GLASS. The barometer rises for northerly wind (including from the north west, by the north, to the eastward), for dry or less wet weather; for less wind, or for more than one of these changes, except on a few occasions, when rain, hail or snow comes from the northward with strong wind.

The barometer falls for southerly wind (including from the southeast, by the south, to the westward), for wet weather ; for stronger wind, or for more than one of these changes, except on a few occasions, when moderate wind with rain (or snow) comes from the northward.

Rise for northeasterly, NW., N., E. ; dry or less wind, except wet from northeastward.

Fall for southwesterly, SE., S., W. ; wet or more wind, except wet from northeastward.

“When rise begins after low,

Squalls expect and clear blow.

Long foretold-long last,
Short notice-soon past.

First rise after low
Foretells stronger blow."

“When the glass falls low,

Prepare for a blow;
When it rises high,
Let all your kites fly.'

These rules will suit the southern hemisphere exactly, if we put N. for S. and S. for N. throughout.

“First the rain and then the wind,

Topsail sheets and halyards mind;
But when the wind's before the rain
Hoist the topsails up again."

" When wind comes before rain,

Soon you will make sail again ;
When rain comes before wind,
Halyards, sheets and braces mind."

“Mackerel skies and mares' tails

Make tall ships carry low sails."

“A rainbow in the morning

Is the sailor's warning ;
A rainbow at night
Is the shepherd's delight."

“When the sun sets in a clear,

Au easterly wind you need not fear."

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