Darby Creek, % mile eastward of Chester range rear light, has a depth of about 7 feet (2.1 m) for 4 miles above the mouth and 3 feet (0.9 m) for a further distance of about 2 miles to the fork, 1⁄2 mile from the town of Darby. It is used only by small pleasure boats. Five bridges cross the river below the fork. Three of them have draw-openings and the others are fixed. The mean rise and fall of tides is about 52 feet at the mouth, 5 feet at the fork, and nothing at Darby.

Essington is a town on the north side of Delaware River northward of Tinicum Island. There is a depth of 16 feet (4.9 m) at the shipyard wharf and 3 to 7 feet (0.9 to 2.1 m) at the clubhouse wharves. The Philadelphia and Corinthian Yacht Clubs have their waterfront facilities here. This is known as the yacht harbor of Philadelphia. Vessels bound to the town, unless of light draft, must pass around the western end of Tinicum Island. There are several marine railways, the largest has a capacity of 125 tons, and can take out vessels 125 feet long and 11 feet (3.4 m) draft. All kind of yacht and small vessel repairs can be done.

Tinicum Island, 11 miles below Philadelphia, is a long, marshy island with bushes on its western end.

There are several large factory buildings between Thomson and Crab Points, and four wharves, the upper one having a depth of about 29 feet (8.8 m) and the others 8 to 12 feet (2.4 to 3.7 m). The anchorage for loading explosives is south of the main channel, as described on page 76.

A large oil depot and refinery is located east of Bramell Point, and 33 feet (10.1 m) can be carried alongside. In case of emergency fresh water can be supplied.

Billingsport is a village on the southeast side of Delaware River, 1 mile above the upper end of Tinicum Island. At Lodge Point east of Mantua Creek entrance, there is an oil terminal wharf with about 30 feet (9.1 m) at the face.

Mantua Creek, on the southeast side of Delaware River, 1/2 mile above Billingsport, is the approach to the villages of Paulsboro, Mount Royal, and Mantua, 112, 4, and 71/2 miles, respectively, above the entrance. A channel has been dredged from the Delaware River to Parkers Landing at Mount Royal about 4 miles long, and a cut-off has been dredged about 2 miles above. The controlling depth in 1936 was 12.4 feet (3.8 m) from Delaware River to the fertilizer plant; thence 7.9 feet (2.4 m) to Paulsboro; thence 5.5 feet (1.7 m) to Mount Royal; and thence 1.6 feet (0.5 m) to Mantua, the head of navigation. There are jetties on both sides at the entrance with lights at the outer ends, and the channel is buoyed to the fertilizer factory.

The following are the bridges crossing Mantua Creek, the distance in nautical miles above the outer ends of the jetties at the entrance, the least width of the openings, and the headroom, when closed:

Paulsboro (Pa. R. R., swing), 1.2 miles, 35.5 feet, 1.7 feet (0.5 m).
Paulsboro (highway, swing), 1.5 miles, 41 feet, each, 4 feet (1.2 m).
Mount Royal (highway, fixed), 4.4 miles, 60 feet, 12 feet (3.7 m).
Mount Royal (Pa. R. R., fixed), 4.5 miles, 42 feet, 13.5 feet (4.1 m).
Mantua (highway, fixed), 7.5 miles, 66.6 feet, 13.5 feet (4.1 m).
Mantua (R. R., fixed), 7.5 miles, 26 feet, 14 feet (4.3 m).

Tides. The mean range of tides is about 52 feet at the entrance, 42 feet at Paulsboro, 4 feet at Mount Royal, and 212 feet at Mantua. High and low water occur later than at the entrance, as follows: Paulsboro, 20 minutes; Mount Royal, 50 minutes; Mantua, 2 hours and 5 minutes.

Woodbury Creek, on the southeast side of Delaware River, 1 mile southward of the entrance to Schuylkill River, has been improved by dredging a channel 6 feet (1.8 m) deep and 60 feet wide from Delaware River to a highway bridge 1 mile above the entrance, and 6 feet (1.8 m) deep and 40 feet wide to the town of Woodbury, 312 miles above the mouth, with two cut-offs near the mouth and one near the head. The controlling depth in June 1936 was 312 feet (1.1 m) at the mouth, thence 612 feet (2.0 m) to the first bridge, thence 3 feet (0.9 m) to the highway bridge at Woodbury.

Two drawbridges cross the creek. The lower bridge, about 1 mile above the entrance, is a center pier draw with openings 40 feet wide and headroom of 6 feet (1.8 m) at high water when closed; the south opening is the better. The second bridge, 34 mile above the lower one, is a bascule draw with an opening 45 feet wide and a head room of 4 feet (1.2 m) at high water when closed. There is a fixed highway bridge at Woodbury with a headroom of 10 feet (3.0 m) at high water. The dredged channel stops at this bridge and there is little navigation above. The mean rise and fall of tides is 5.3 feet at the entrance and 4 feet at Woodbury. High and low water at Woodbury occur about 34 hour later than at the mouth.

There is a middle ground in Delaware River northwestward of the entrance to Woodbury Creek, which is marked on the southwest end by Block Island Light (flashing white, with red sector). The structure is a white square skeleton tower on cylindrical base. Vessels bound into Woodbury Creek can pass on either side of the middle ground. The channel at the entrance is buoyed, but some local knowledge is necessary to enter with the best water.

Vessels approaching Woodbury Creek from southwestward should pass 400 yards southwestward and southward of Block Island. Aproaching from northward, eastward of the middle ground, pass 100 to 200 yards off the wharf at Philadelphia Sanitarium, 350 yards offshore abreast the white monument at Red Bank, and 550 yards off the mouth of the creek. The course in the channel into the entrance passing on the north side of the two buoys (with red reflector) is 125° true (SE. % E. mag.) to the entrance. At low water the channel in the creek is well defined.

PORT OF PHILADELPHIA

(Charts 280, 295, and 296)

The port of Philadelphia (State of Pennsylvania Authority) officially includes the Delaware River from Marcus Hook to Morrisville, Pennsylvania.

The harbor of Philadelphia embraces the Delaware River from the mouth of the Schuylkill River to the Pennsylvania Railroad bridge in the upper part of the city, a distance of 12.5 statute miles, and the Schuylkill River as far as the Fairmount Dam, a distance of 8.6 miles.

Immigration service. The United States immigration station for the port of Philadelphia, and other ports of the Delaware River, is located at Gloucester, N. J., directly opposite Philadelphia on the Delaware River. Immigration inspections are made of all vessels arriving from foreign ports.

Customs service. The customhouse is located at Chestnut and Second Streets, and is open from 9 a. m. to 4.30 p. m., except on Saturday, when it is open until noon. Vessels may clear between these hours, or by special arrangement with the customs officials.

Quarantine service. This is furnished by the United States Public Health Service at Marcus Hook, Pa. for all Delaware River ports above Wilmington, Del. (See p. 79.) Fumigation can be done with cyanide, requiring 6 hours. There is a relief station of the Public Health Service at 225 Chestnut Street, Philadelphia.

Railroads. Three important railroad systems and one belt line railroad serve the port of Philadelphia, as follows: The Philadelphia & Reading, the Pennsylvania, the Baltimore & Ohio, and the Philadelphia Belt Line Railroad. The latter waterfront system is controlled by the city and is open to all the railroads on equal terms. All ocean and coastwise steamship lines have direct communication with one or more of the railroads serving this port.

Oil bunkering.-There are facilities at Point Breeze and Petty Island in the harbor of Philadelphia and at Paulsboro, N. J., Chester, Pa., Marcus Hook, Pa., Claymont, Del., and Wilmington, Del., for supplying oil-burning vessels with fuel.

Coal bunkering.-There are several companies engaged in bunkering vessels with coal. Vessels as a rule are bunkered from barges while at their regular berths loading cargo. There are large coal dumping facilities at Greenwich Point and at Port Richmond. The former has a wharf with a depth of 36 feet (11 m), and the latter has wharves with depths from 15 to 30 feet (4.6 to 9.1 m).

Dry docks and marine railways.-With the exception of those at the navy yard there is only one graving dock at Philadelphia and neighboring localities of sufficient capacity for docking a ship 428 feet long. (For additional data see under Camden.) One of the marine railways can accommodate a ship of 288 feet long, and has a lifting capacity of 1,500 tons. There are numerous marine railways suitable for hauling out the smaller types of vessels.

Airports. Philadephia has several landing fields. The largest is the Philadelphia-Camden Central airport 411⁄2 miles from the center of the city and located in Camden, New Jersey.

Commerce. The imports of raw materials are mainly iron ore, sugar, petroleum and its products, manganese ore, sulphur, and nitrates of soda. This represents about 60 per cent of the imports. Exports are made up mostly of heavy commodities, such as petroleum and its products, coal, grain, flour, iron and steel, lumber, and manufactured articles.

Domestic commerce consists mainly of coal, sand, gravel, petroleum and its products, sugar, fertilizers, besides the local business of the Delaware Bay and River.

In 1934 the total of all this commerce amounted to 28,705,000 tons. Holidays. The following holidays are observed: New Year's Day (January 1); Lincoln's Birthday (February 12); Washington's Birthday (February 22); Good Friday (Friday before Easter Sun

day); Memorial Day (May 30); Independence Day (July 4); Labor Day (first Monday in September); Columbus Day (October 12); Armistice Day (November 11); Thanksgiving Day (last Thursday in November); and Christmas Day (December 25).

For Harbor and Anchorage Regulations, and for Speed Regulations see the appendix. For anchorages see page 362.

Wharves. The wharves and piers on the Philadelphia side of the Delaware River are numbered consecutively from the foot of Market Street northward to Port Richmond and southward to Greenwich Point. The wharves at Port Richmond are numbered independently. Those on the west side of the river, including Petty Island, and the east side opposite Philadelphia have depths of 5 to 38 feet (1.5 to 11.6 m) at mean low water. On the Schuylkill River there are depths of 3 to 30 feet (0.9 to 9.1 m) at the wharves. There are several municipal piers equipped with modern freight handling equipment.

The wharves on the Camden side are numbered consecutively from Pavonia southward to Newton Creek, except for the Pennsylvania Railroad wharves, which are numbered independently.

Tides. The mean range of tides at Philadelphia is 5.2 feet. Daily predictions are given in the tide tables published annually by the Coast and Geodetic Survey.

Schuylkill River, emptying into Delaware River at the lower end of the city of Philadelphia and at the western end of League Island, is navigable to the entrance of the Schuylkill Navigation Canal, near the Fairmount Dam, 712 miles above the entrance. It is an important outlet for a part of the commerce of Philadelphia. There are large grain elevators at Girard Point, oil-refinery wharves opposite Point Breeze and at Gibsons Point, and other industrial wharves, besides several yacht clubs.

The dredging project in Schuylkill River provides for a channel 30 feet (9.1 m) deep at mean low water and 400 feet wide to Twenty-ninth Street, thence 30 feet (9.1 m) deep and 300 feet wide to Passyunk Avenue, thence 26 feet (7.9 m) deep and 200 feet wide to Gibson Point, and thence 22 feet (6.7 m) deep and 200 feet wide to University Avenue. The restoration of the channel to project dimensions from the Delaware River to University Avenue has been completed, but rapid shoaling necessitates frequent redredging. examination in 1936 showed a controlling depth of 28 feet (8.6 m) to Passyunk Avenue, thence 18.8 feet (5.7 m) to Gibson Point, and thence 12.2 feet (3.7 m) to University Avenue.

An

The channel in the Schuylkill River is crooked but is marked by an entrance range and by buoys as far as the Baltimore & Ohio Railroad bridge. Above this point chart 280 is the best guide. A light marks the outer end of the sunken jetty at the mouth. An electric siren is located on the wharf end at Fort Mifflin and a bell at the entrance to the river. A black buoy off the mouth of Mingo Creek marks a rock with 8 feet (2.4 m) over it. Anchorage in Schuylkill River is prohibited except by permission of the commissioners of navigation. The mean range of tides is about 512 feet.

Schuylkill Navigation Canal is a succession of short canals and slackwater pools following the course of the Schuylkill River from a point near Fairmount Dam, 71⁄2 miles above the entrance, to Port Clinton,

a distance of about 80 miles. The lock at the dam has been filled in and there is no navigation connection now. The available depth at low stage to Phoenixville, 23 nautical miles, is about 4 feet (1.2 m). There is no navigation above this town, the canal from here to Port Clinton having been out of use since 1919. There are 12 locks to Phoenixville, each 18 feet wide, 110 feet long and 6 feet (1.8 m) over the sill. All of the bridges crossing the canal are fixed, the lowest being a bridge at Norristown, 13 miles above the dam, which has a headroom of 13 feet (4.0 m) at mean summer stage and 1 foot (0.3 m) at flood stage. The canal is closed for about 4 months in winter. It is used mostly by yachts and motor boats.

Bridges. The following are the bridges below the dam crossing the Schuylkill River, the distance in nautical miles above the entrance, the width of the openings, and headroom above high water (draw closed):

Penrose Avenue Ferry (highway, swing), 1.1 miles, 183 feet each, 18 feet (5.5 m).

Passyunk Avenue (highway, bascule), 3.0 miles, 200 feet, 34 feet (10.4 m). Baltimore & Ohio Railroad (swing), 4.4 miles, 57 feet, each, 15 feet (4.6 m). Grays Ferry Avenue (R. R., swing), 4.7 miles, 75 and 65 feet, 221⁄2 feet (6.9 m).

Grays Ferry Avenue (highway, swing), 4.7 miles, 75 feet, each, 221⁄2 feet (6.9 m).

University Avenue (highway, bascule), 5.3 miles, 100 feet, and 87 feet, each, 33 feet (10.1 m).

Pennsylvania Railroad (swing), 5.5 miles, 70 and 67 feet, each, 26 feet (7.9 m).

South Street (highway, bascule), 5.8 miles, 100 feet, and 1011⁄2 feet, each, 37 feet (11.3 m).

Walnut Street (highway, fixed), 6.2 miles, 113 feet, and 95 feet, each, 22 feet (6.7 m).

Chestnut Street (highway, fixed), 6.3 miles, 160 feet, each, 32 feet (9.8 m). Market Street (highway, fixed), 6.4 miles, 164 feet, each, 28 feet (8.5 m). Market Street (R. R., fixed), 6.4 miles, 200 feet, and 69 feet, each, 29 feet (8.8 m).

Arch Street (R. R., fixed), 6.5 miles, 172 feet, each, 38 feet (11.6 m).

Spring Garden Street (highway, fixed), 7.0 miles, 280 feet, 17 feet (5.2 m). Bridge regulations prescribed for the drawbridges crossing the Schuylkill River require that they shall be opened at all times during the day or night to all vessels that can not pass underneath them, if no person or vehicle passing over the bridge is then in the way or a railroad train is on the bridge or within 5 minutes of the schedule time of a passenger train. The signal is three blasts of a whistle or horn, to be answered from the bridge by two blasts if the bridge can be opened immediately, or one blast if the bridge can not be opened immediately. The draw need not be opened for the passage of a tug or other craft equipped with a smokestack which can be lowered so as to permit passage under the closed draw.

League Island, at the junction of the Delaware and Schuylkill Rivers, is the site of a United States navy yard. The basin on the north side of the island and its entrance from Schuylkill River have been dredged to a depth of 30 feet (9.1 m) but has shoaled to 16 and 18 feet (4.9 and 5.5 m) in the entrance. It has shoaled a lesser amount inside. The depths at the wharves are about 20 to 30 feet (6.1 to 9.1 m). The wharves on the south side of the island range in depth from 6 to 35 feet (1.8 to 10.7 m). There are protection lights on the radio towers and the crane on pier 8.