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The foundation of pier No. 9 rests on 2 feet of concrete, which is laid on sand. All the other foundations consist of three courses of timber, of 1 foot each in thickness. We have received the following account of the work of laying these foundations: The pier foundations were commenced in August, 1869, and piers Nos. 1, 2, and 7 were put in before the close of the season. These were out of the water, and only required simple excavations. During the same time the coffer-dam at No. 5 was commenced. This was a double frame filled with puddling. Work was continued on the coffer-dam until high water stopped operations. In the spring of 1870 the programme was changed, and the coffer-dams used were constructed of sheet-piling 4 inches thick, put down in single rows and calked, the lower ends of the piles being shod with iron. They were put in place, and paddling of mud, &c., piled about the foot on the outside to a height of about 10 feet, with the natural slope. This was found not to accomplish the object of keeping out the water, until the entire bottom, on all sides for a distance of 75 feet, was covered, to the depth of 3 feet, with clay, and an embankment of clay was built up on the outside to the surface of the water. The work of excavation was carried down through the gravel bottom of the river, to the rock in place at pier No. 3, and to heavy limestone boulders, supposed to rest on the rock at the other piers. It was found impossible to excavate to the rock in place by the method pursued. Pier No. 3 was put in while the water was 9 feet above the zero of the water-works. Piers Nos. 5 and 6 are thought to be within 3 feet of the rock. It is thought that a much cheaper and better method of building these piers would have been to dredge out the place for the foundation, and to lay the masonry in caissons. A permanent protection to the foundations remains to be made. The space around each pier should be covered with riprap for a width of 40 feet; under no circumstances coming higher than 3 feet below low water. No stone should be used of less size than two perches, or 50 cubic feet, and they should be laid in contact and well fastened together.

The material in the bed of the river, in the order in which it is met, is one foot of coarse sand with small boulders, two feet of coarse gravel, and then flat stones, that seem to have once been in motion along the bed of the rock beneath.

The brick-work of the approaches is of medium quality, trimmed in part with stone. The foundations of the arches, in some cases, seem to have yielded, causing cracks. Some of the bricks will be submerged in high water, a test to which its quality does not well adapt it.

The wooden trestle-work of the railroad approach on the Cincinnati side is of the ordinary kind, and is temporary in its character.

The following estimate of the cost of the substructure, on the present plan, we have made ourselves, with as much care as possible, having failed to get any such information or estimate from the bridge company:

Pier No. 1. Excavation for foundation above water, 490 cubic

yards, at 75 cents....

Timber grillage, 1,600 cubic feet, at 30 cents

833 cubic yards masonry, including cut stone, at $18

Pier No. 2. Excavation for foundation above water, 540 cubic yards, at 75 cents....

Timber grillage, 2,880 cubic feet, at 30 cents....

$368 00 400 00 14,994 00

$15, 842 00

405 00

864 00

1,160 cubic yards of masonry, including cut stone, at $18..

20,880 00

Pier No. 8..

22, 149 00 22,149 00

Pier No. 3. Preparing and placing foundation. 3,843 cubic feet of timber for grillage, at 30 cents Riprap protection of large blocks, clamped..

7,500 00
1, 153 00
7,500 00

1,290 cubic yards masonry, including cut stone, at $18.

23, 220 00

39, 373 00

Pier No. 4..

39, 373 00

Pier No. 5. Preparing and placing foundation..

7,500 00

Riprap protection

4,000 00

Excavation for foundation above water, 540 cubic yards, at 75

cents

405 00

Timber grillage, 2,880 cubic feet, at 30 cents

864 00

1,160 cubic yards of masonry, including cut stone, at $18.

20,880 00

Pier No. 7.

33, 649 00 33,649 00

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432,000 feet, board measure, of timber, in crib of pivot-guard, framed and bolted, at $40..

10,000 00

45, 000 00

17,280 00

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$4,650 00

8,000 pounds iron plate for sheathing to ice-breaker, at 10 cents

800 00

54,000 feet timber for guide-float, at $40

2, 160 00

$94,200 00

Pier No. 9. Excavation for foundation above water, 360 cubic yards, at 50 cents....

180 00

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Approach for railroad and wagon-road on Newport side from

main abutment on Market street:

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Approach for railroad in Newport between Market and
Southgate streets:

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772 feet rails, 2571 yards, (at 60pounds per yard)=15,440 pounds,

at $35 per ton....

656 00

193 ties, at 50 cents..

96 00

9,516 00

Total cost of approaches on Newport side

34,998 00

Cincinnati approach for railroad and wagon-way from abut

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20 cubic yards concrete, at $6.....

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64,000 feet lumber in trestles, framed and erected, allowing for

2,000 feet of road, requiring 1,333 yards of rails, at 60 pounds

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DESCRIPTION OF THE SUPERSTRUCTURE OF THE NEWPORT AND CINCINNATI BRIDGE, AND ESTIMATE OF ITS COST WHEN COMPLETED ACCORDING TO PRESENT DESIGN.

The charters of this bridge, obtained from the legislatures of Ohio and Kentucky, leave it optional with the company to construct any kind of bridge which they may select that will not obstruct the navigation of the river more than is authorized by the laws of the United States.

The ordinance of the city of Newport, granting the use of portions of the streets for the purpose of a bridge, makes one of the terms of the grant that said bridge shall be constructed and used for "the passage of vehicles and foot-passengers across the Ohio River, and for railroad purposes." It therefore became necessary, if the bridge was to be built within the limits of the city of Newport, to construct it as a combined wagon and railway bridge. The trusses are being built by the Keystone Bridge Company after their usual designs.

The plan of superstructure adopted is to place the two trusses so close as to allow a clear space of 13 feet for the passage of trains. This is the very least that will admit the largest-size passenger-cars capable of using the Little Miami gauge of 4 feet of inches.

The floor-beams are of iron, suspended generally from the lower ends of each post, and projecting each side of the truss so as to permit of a wagon-way 6 feet wide, and a sidewalk 3 feet wide, the space outside of the trusses being 10 feet. The superstructure is thus 384 feet in width over all. The railroad-track rests on the suspended iron floorbeams, except for two spans on the Cincinnati side and one span on the Newport side, in which spans the railroad-track is supported on separate floor-beams, intermediate between the top and bottom chords. These spans are further peculiar in having a horizontal top chord, with the lower chord on the grade of the wagon-road approaches, to wit, on a slope of 5,637 feet to 100.

The tops of the piers are 73 feet above low water, but as the floor-beams are 14 feet deep, suspended below the bottom chord, there is left an unobstructed headway of 714 feet.

The drawings which we have received show the proposed arrangement of the first two spans on the Cincinnati side. The trusses already erected over the space between piers Nos. 7 and 8 show us what that span is to be. We have also been furnished with drawings of the pivot or draw span. Thus far we have not been informed of the moving load the bridge is designed to support. It is probable, however, that an allowance of load equal to 2,500 pounds per lineal foot of the railroad, and 100 pounds per square foot of the wagon-road, and 75 pounds per square foot of sidewalk, has been provided for. The load to be sustained outside of the trusses is, therefore, about 1,575 pounds per lineal foot, making the total of the moving load 4,075 pounds per lineal foot. The width of roadway and sidewalk is very small, and the arrangement for wagon-way alongside of the railway is very objectionable. The sum of the weights of roadway bearers for both kinds of roads, longitudinal beams, railroad ties and rails, wagon-road floor, and hand-rails, is about 1,000 pounds per lineal foot of bridge. From these we obtain the proper elements for calculating the dimensions of the trusses required for supporting these permanent and rolling loads. The bridge company not having furnished us with any statement of the cost of making the trusses, we have made out calculations on the basis of the cost of the bridges heretofore built by the Keystone Bridge Company, and have allowed market rates for the kind of work required.

The following is an estimate of the cost of the superstructure, as now being built, from abutment to abutment, a distance of 1,782 feet:

Estimate of cost of superstructure of bridge, as being built, including roadways, rails, siderails, &c., complete.

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One span, 1374 feet

79,000 00

One span, 132 feet, including bottom chord and double roadway bearers.
Two spans, 96 feet, including bottom chord and double roadway bearers.

13,500 00

16,000 00

14,000 00

Total...

375,500 00

EFFECT WHICH THE BRIDGE, AS NOW BEING CONSTRUCTED, WILL HAVE UPON THE NAVIGATION OF THE OHIO RIVER.

The objections urged by those interested in the navigation of the Ohio River against the Newport and Cincinnati bridge, are as follows:

1st. That the bridge is too low.

2d. That the character of the commerce of the Ohio River is such that no draw-bridge can be made at Cincinnati that will not seriously obstruct navigation.

3d. That the channel-span is so located that it is difficult to reach and dangerous to

run.

The question of the proper height for a bridge at Cincinnati to connect that city with Covington was agitated for many years, and the existing suspension-bridge is the result of a compromise between the interests involved. For a long time the river-men would not agree to a less height than 125 feet, with a span equal to the average width of the river. As a bridge of such great height could not be built with practicable grades for vehicles without excessive cost and limited usefulness, a compromise was finally effected, in accordance with which the present structure was erected, with a height of 103 feet at the crown and a clear span of 1,000 feet. But even this bridge is somewhat of an obstacle, as in high water the larger-sized steamers cannot pass under it, and the velocity of the current is perceptibly increased by the contraction of the water-way by its two piers. But the river interest concedes the fact that it must submit to some inconveniences for the general public good, and the compromise which resulted in the erection of this suspension-bridge has been generally accepted as equitable to all parties. The result is that the bridge has been taken as the boundary between the up-stream and the down-stream traffic, one class of boats having permanent landings above the bridge and the other below.

Comparing this bridge with that now being built between Newport and Cincinnati, we find that the latter is 314 feet lower, with a maximum channel-span of 400 instead of 1,000 feet.

The Newport and Cincinnati bridge is 714 feet above low water, or 9 feet_above extreme high water, the maximum difference between high and low water at Cincinnati being 624 feet. It is manifest that in extreme high water nothing but low flats or rafts could pass under the bridge.

In order to show what depth of water may be expected at Cincinnati, we have carefully compiled the following table from the official records of the city, as kept at the water-works office, since the 1st of June, 1858, being taken twice each day, and covering a period of over twelve years. The heights given are those above the official "O," which shows dead low water, at which time there is 14 feet of water on Four-mile Bar above, and on Rising-Sun Bar below. The figures show the number of days in each • month during which there is in the river the specified number of feet above low water: River-record at Cincinnati.

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When the river at Cincinnati is 5 feet above low water, there is 5 feet on the bars above and below. When there is 10 feet, the same bars show 9 feet of water, and at 15 feet by the water-works marks, they can be crossed by boats drawing 12 feet. As they are the ruling bars for long distances above and below, the depths on them show the

capacity of the river at these stages. A good coal-boat rise of 8 feet at Pittsburgh generally gives from 12 to 20 feet at Cincinnati, depending upon the time of the year.

The last two lines of the table show the absolute space under the bridge at these stages, and the greatest available space, allowing 14 feet for clearance, which is the least margin that could safely be taken.

The dimensions of some of the largest packets, at present regularly employed on the river above Cincinnati, are as follows:

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The Fleetwood and Telegraph are regular up-river packets, running to Pomeroy and the Big Sandy. The record shows that during one hundred and fifteen days in each year the former could not get under the bridge, even with lowered chimneys, and that the latter would be similarly stopped during one hundred and nine days. The St. Charles is a regular Pittsburgh and Cincinnati packet, and she would be compelled to use the draw during one hundred and seven days. Without lowering their chimneys none of these boats could get under the bridge at all, as those of the first two are higher than the bottom chord of the bridge at dead low water, and the latter, whose chimneys have lately been shortened 8 feet, could only get under the bridge at a stage of water when she could not run at all. The Juniata, St. Mary's, and Arlington, the consorts of the St. Charles in the Pittsburgh and Cincinnati Packet Line, are all side-wheel steamers of about the same size. There are other packets as large, and others somewhat smaller, that regularly or occasionally ply up the river, but those mentioned are about the largest.

The tops of the chimneys, when lowered as at present arranged, come about 6 feet above the pilot-houses, in order to secure leverage for the shears when raising them into place, and in order to get the smoke out of the eyes of the pilot at the wheel. But it is believed that they can be still further lowered by improved mechanical appliances, and that the pilot-houses may be moved sufficiently forward to get out of the smoke. The mere lowering of the chimneys of a first-class boat, some of which are 54 feet in diameter, is a job of considerable difficulty, not unattended, at times, with danger.

The position of the pilot-house of a western steamer is a matter of great importance, in order that the pilot may see the water as near the bow and stern and sides of his boat as possible. The most elevated position practicable is also required, in order to see distinctly the water-surface, which, to the trained eye, indicates with great precision the outlines of shoals, sunken rocks, wrecks, and snags. In the Missouri River, where the channel changes every two weeks, pilots run entirely by the appearance of the water, and the higher they are above it the more clearly they can see and interpret its variations. Then, again, western rivers are often covered with dense, low-lying fogs, which are impenetrable at the level of the main deck, but often do not rise to the height of the pilot-house. Long experience has shown the necessity of the high pilothouse, and it cannot be lowered without great injury to navigation.

However inconvenient and dangerous the draw may be, yet individual boats can get through it in some way or other, though not without both delay and danger. It is very narrow, only 100 feet in width, being 60 feet less than that prescribed by Congress for the bridges over the Mississippi, and the cross-currents formed in so contracted an opening by the deflection of the current from the pivot-guard and by the obliquity of the piers, will make its passage very hazardous. Moreover, the narrowness of the water-way at Cincinnati, which causes the exceptional height of high water, also greatly increases the surface velocity, making the passage of narrow places more dangerous than it would be at any other point on the river.

No boat would dare attempt to get through from above without rounding to and backing, and, if possible, getting a line to the pivot-guard and letting itself drop through. This is a delicate operation, even in day-time, as the guard-pier is so near the pivot-pier, but at night it is almost an impracticable one. Most captains and owners had sooner tie up above the city until morning rather than risk their boats by a night passage of this draw.

Such losses of time are serious losses of money, and the annoyances to passengers thus stopped while almost at their journey's end would appreciably affect the river-travel. But there is a large and increasing class of traffic on the Ohio River, to which the draw is almost an impassable barrier when the river is too high to pass under the bridge.

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