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Development of Early Transportation Systems in the United States
THE entire subject of erecting railway bridges over navigable waters
assumed a new aspect during the seventh decade, on account of the
development of an imperative necessity for improving the channels of
communication between the states east and west of the Mississippi and
Missouri rivers, and the states north and south of the Ohio, and
congressional action, which gave a more distinct and emphatic authorization
of bridge projects than had previously been procured.
CONFLICT OF RAIL AND RIVER INTERESTS
Bitter controversies had grown up between representatives of overland and
river interests, on account of obstructions to navigation which had been
created by a highway draw-bridge over the Ohio at Wheeling, and the railway
draw-bridge erected over the Mississippi, between Rock Island and
Davenport, without congressional authority. Under the old system, few
companies cared to undertake the construction of bridges over either of the
great western rivers at any point, and no legal sanction for such
enterprises was deemed necessary except such as could be procured from
state legislatures. The modern usage, when navigable streams form a
boundary line between states, is to require congressional sanction for the
bridges erected over them, which is sometimes supplemented by favorable
action of both the states interested.
The first series of
CONGRESSIONAL BRIDGE LAWS
of material significance were passed during the seventh decade. They were
based on the theory that railway bridges might be built at the points named
in the various enactments, provided a design and style of construction was
adopted which would avoid serious obstructions to navigation. This
exception left a large field for controversy, as the navigable interests
included not only steamboats, some of which formerly had pi1ot houses and
chimneys at a great height above the water, but also tows of barges and
large rafts which required for their successful operation a wide distance
between piers. The steamboat men claimed that high chimneys were of great
service, for the double purpose of giving draught, and either cooling
sparks as they ascended to great heights, or preventing them from
engendering fires as they fell on decks. One steamboat, the James Howard,
built for service on the dower Mississippi in 1874, which had no bridges to
encounter, kind chimneys 104 feet above the water, and it was reported that
the chimneys of the Great Republic reached a still higher altitude. The
general range of the height of chimneys on the large Mississippi river
boats, which formerly passed St. Louis, was from 65 to a little more than
90 feet; and the top of their pilot houses was from 46 to 69 feet above
water. As the waters of the western rivers occasionally rise many feet
above the normal standard, and it was necessary that provision should be
made for operations during high-water periods, it is obvious that it would
be exceedingly difficult, or practically impossible, to construct bridges
at a number of points where they were desirable which would not obstruct
the passage of boats having chimneys 100 feet high, unless they were
drawbridges. The advocates of bridges insisted that excessively high
chimneys were not absolutely necessary, and important concessions relating
to the height of bridges were obtained.
Other difficulties arose out of the requirements of the barge system for a
wide space between the piers of any bridge that might be erected. At the
time the bridging of the Ohio at Steubenville was authorized, in 1862, the
barge system or combinations of flats and barges used in the transportation
of coal had come into such extensive use on the Ohio that a congressional
enactment required a width of not less than 300 feet in the clear between
piers, and the coal navigation interests endeavored to secure a space of
not less than 500 feet. Subsequent laws of Congress require spans of not
less than 400 feet in the clear on the Ohio below the mouth of the Big
Sandy river, and bridges across the Ohio giving a clear span of 500 feet
were built. A wide space between spans was peculiarly desirable on the Ohio
on account of the magnitude of the coal tows on that river.
On the Upper Mississippi the rafting interest was formerly very important,
and on that account, as well as on account of the demands of steamboat
interests, a wide space between piers was considered desirable, but the
characteristics of that stream at many points are deemed unusually
favorable for bridging, in comparison with other rivers of equal magnitude,
and especially the Missouri.
Supervision over the erection of bridges across navigable waters, in
accordance with acts of Congress, was commenced by the United States
engineers in the seventh decade, and has been continued since, and their
views or recommendations have exercised an important but not always a
controlling, influence over the final decision of the numerous disputes
between representatives of conflicting rail and river interests which have
arisen.
RAILWAY BRIDGES AUTHORIZED BY CONGRESS IN THE SEVENTH DECADE.
The list of bridges over navigable waters authorized by Congress during the
seventh decade, or in early years of the eighth decade bridges deface which
bridges was generally, but not in tonic, the Mohawk, the soon after their
construction was rivers which so usually, but not always, railway all
suffer by the vile wood of railway and highway bridges, in that all to
plead in extensive subject to various restrictions and of the points named
below:
Every bridge in this country Steubenville, or any point above the mouth of
the Big Sandy river; between Cincinnati, Ohio, and Covington, Kentucky; at
Louisville, Kentucky, Wheeling, W. Virginia.
Over the Mississippi River.-At Quincy, Illinois; Burlington, Iowa; Prairie
du Chien, Wisconsin; Keokuk, Iowa; Winona, Minnesota; Dubuque, Iowa; St.
Louis, Missouri; Clinton, Iowa; Rock Island, Iowa (as a substitute for the
bridge first erected by the Chicago and Rock Island Railroad Company); La
Crosse Wisconsin; Muscatine, Iowa; at any point between the counties of
Whitesides and Carroll, Illinois, and Jackson and Clinton, Iowa; Hudson,
Wisconsin; Warsaw, Illinois; Fort Madison, Iowa; Red Wing, Minnesota;
Lexington, Missouri.
Over the Missouri River.-At any point necessary for convenience by the
Union Pacific and Hannibal and St. Joseph railway companies; at Kansas
City; Fort Leavenworth, Kansas; St. Joseph, Missouri; Omaha, Nebraska;
Louisiana, Missouri; Glasgow, Missouri; Boonville, Missouri; Nebraska City,
Nebraska; Brownville, Nebraska; Sioux City, Iowa.
The authorization of additional bridge structures over the navigable waters
named above, and other streams, has since formed an important portion of
the labors of a number of sessions of Congress.
THE SPECIFIC RESTRICTIONS AND REQUIREMENTS IMPOSED BY CONGRESS,
in connection with the grants of authority to construct bridges have varied
materially, on account of the differences in the requirements of river
interests at various points, or other causes.
The leading provisions of an act passed in 1866 authorizing the
construction of eight bridges on the Mississippi and one on the Missouri
were that if built as high bridges they should be 50 feet above extreme
high-water marl, with spans not less than 250 feet in length, and one main
or channel span not less than 300 feet in length. If built as draw-bridges,
they should have two draw openings of not less than 160 feet in the clear,
and next adjoining spans of not less than 250 feet, and should be 10 feet
above high-water mark, and at least 30 feet above low-water mark.
Provisions similar to those enumerated above were applied to a number of
bridges over the Missouri river.
In reference to the construction of a bridge at St. Louis which was one of
the bridges authorized by this act, the law provided that it should not be
either a suspension bridge or a draw-bridge, but that it should have
continuous or unbroken spans, with the bottom chord 50 feet above the city
directrix at its greatest span; that it should have at least one span of
500 feet in the clear, or two spans of 350 feet in the clear, and that no
span over the water at low-water mark should be less than 200 feet in the
clear. A later act required that the bridge at St. Louis should have one
span of at least 500 feet in the clear.
In reference to bridges over the Ohio the provisions for the Steubenville
bridge were that it should leave an unobstructed headway in the channel of
the river of not less than 90 feet above low-water mark, and an
unobstructed width of not less shall 300 feet between the piers next to
said channel or waterway; and one of the spans next adjoining that should
not be less than 220 feet in length. The law required that if it was built
as a high bridge it should be not less than 90 feet above low water over
the channel, and if built as a draw-bridge it should be constructed with a
span over the main channel 300 feet in length and not less than 70 feet
above low-water mark, and one of the adjoining spans not less than 220
feet, and also that there should be constructed a pivot-draw in every such
bridge in a navigable part, with spans of not less than 100 feet on each
side of the pivot. A law passed in 1871 made it unlawful to proceed with
the construction of a bridge then being built between Cincinnati and
Covington unless the channel span of 400 feet, as located, should have a
clear headway at low water of 100 feet below any part of the span. Various
other acts were passed in the early years of the eighth decade which
insisted upon requirements more favorable to river interests than those
which had been deemed necessary during the seventh decade.
THE BRIDGE WORK COMPLETED
in accordance with the above enactments, either before 1870 or a few years
later, included railway bridges over the Ohio at Steubenville, Bellaire,
Parkersburg, Cincinnati, and Louisville, which were important and expensive
structures.
The bridge erected over the Ohio at Louisville connected the Jefferson,
Madison and Indianapolis Railroad, which, as well the bridge, forms part of
the Pennsylvania system, with the Louisville and Nashville Railroad. Its
total length is 5,294 feet, consisting of twenty-seven spans, of various
lengths, from 50 to 250 feet, on the Fink plan, placed below the grade of
the road, and two channel spans, one 370 and the other 400 feet long,
placed above the grade of the road. The bridge was commenced in the fall of
1867, and completed in the spring of 1870. The channel spans are of a
peculiar design, a modification of the triangular plan of bracing, by
introducing auxiliary trusses between the main braces. The feet of the main
braces 56 feet 71/4 inches apart, and by the auxiliary trusses this space
is divided into four parts, giving a support to the stringers, upon which
the track rests, every 14 feet 13/4 inches. The height of the truss is 46
feet. Each side of the bridge consists of two separate trusses, which are
simply bolted together. The chords are of cast iron, the braces having to
resist compression of wrought iron, and the tension members also of wrought
iron. The following is a statement of the quantity of iron in some of the
principal spans:
The Newport and Cincinnati bridge, crossing the Ohio river at Cincinnati, and furnishing connection between north and south railways converging at Cincinnati, as well as a highway or common road connection between the cities named above, belongs to the Pennsylvania system. It also owns or controls the Steubenville bridge. The Ohio was bridged by the Baltimore and Ohio at Bellaire and Pittsburgh, by expensive structures. Bridges over the Missouri at St. Charles, Boonville, Kansas City, Leavenworth, Atchison, St. Joseph, and Nebraska were finished by or before January, 1874. The St. Charles bridge was commenced in 1868 and finished in 1871, at a cost of $1,797,186.19. It is regarded as an admirable structure, designed by Gen. C. Shaler Smith, and built by Smith & Latrobe, Baltimore Bridge Company. The bridges at Boonville, Kansas City, Atchison, and St. Joseph were all railway draw-bridges. The bridges at Leavenworth and Omaha were elevated railway bridges. The list of bridges erected over the Mississippi either before or shortly after 1870 includes the following:
It will be seen by the above list that nearly all the bridges enumerated were draw-bridges, but one was a pontoon bridge of novel design, and another the famous elevated bridge at St. Louis. THE MISSISSIPPI RIVER DRAW-BRIDGES varied considerably in their superstructure, wood being the principal material in some instances and iron in others, and also in the arrangement of their draws, piers, and spans. Some of the bridges were built by private bridge companies, others by railway companies, and one, the new Rock Island bridge, under the direction of the United States engineers, acting on behalf of the United States government. Some of the bridges were crossed only by the trains of one railway company, and others by the trains of several companies. On account of the magnitude of the labors involved, a number of the bridge-contracting companies of the country, including the American Bridge Company, of Chicago; the Keystone Bridge Company, of Pittsburgh; the Detroit Bridge Company; the Phoenixville Bridge Company; the Baltimore Bridge Company; the Detroit Bridge and Iron Works, and the Kellogg Bridge Company, of Buffalo, furnished portions or all of the superstructure of one or more of the Mississippi river bridges. The bridge with the longest draw-span, and with what was the longest draw-span in the United States at the time of its construction, was the Louisiana Railway bridge at Louisiana, Missouri. The river at that point is about 3,700 feet wide at low water, and the high-water width is several miles. Commencing on the right bank, the abutment is approached by an embankment, 450 feet of which are in the low water. The first span is 162 feet to the centre of the draw, west pier; then a draw span 444 feet over all, with two clear openings of 200 feet each; then a span 256 feet; then one of 2261/2 feet, and then six spans of about 161 feet each from centre of piers, making a total length of bridge of 2,053 feet. From the Illinois end of the bridge there is 2,200 feet of embankment. The piers are of masonry. The superstructure is of wrought iron, except in some minor parts. THE PONTOON BRIDGE at Prairie Du Chien was designed and constructed by Mr. John Lawler, to meet the particular wants of that locality. It is built at a point where the river is divided by an island and is about 11/4 miles in width from shore to shore. Formerly passenger and freight cars were transferred by ferry boats which had to go around the head or foot of the island, making the distance from landing to landing nearly four miles; and when floating ice accumulated the river was frequently impassable. The construction of a bridge of either of the standard descriptions would have been peculiarly difficult or expensive. These circumstances led to the adoption of a system under which the bridge approaches on either shore, and the fixed portions of the bridge in low water and on the island, consist of piles, while in the channels of the river pontoons are placed, which are so combined and arranged as to form a railway bridge when the passage of trains is desirable; while when the use of the channels by steamboats or rafts is necessary the pontoons are temporarily removed. The pontoon in the east channel is made by uniting three ordinary transfer scows which have an aggregate length of 393 feet, and the pontoon in the west channel is a single-deck scow especially constructed for the purpose, 408 feet long, 28 feet beam, and 6 feet in depth. Applications for the right to construct bridges of a similar plan at various other points on the Mississippi and elsewhere have been made and granted. THE ELEVATED RAILWAY AND HIGHWAY BRIDGE AT ST. LOUIS was, at the time of its completion, the most expensive bridge that had then been constructed in the United States. Its cost, including approaches, tunnel and land damages, legal expenses, discounts, commissions on bonds, &c., was $12,680,333.47. The width of the river at the point of construction is about 1,200 feet at low water and 1,900 feet at high water. Considerable difficulty was experienced in procuring a foundation for the piers and abutments on the bed rock of the river, but by means of inverted caissons and the plenum pneumatic process they were all surmounted. The abutments are placed on the margin of the water at ordinary low stage, with two piers in the channel way. The three spaces thus left are spanned by circular segment arches. The middle one has a chord of 515 feet, and the crown of the arch is 55 feet above the city directrix, which is 331/2 above low water. The superstructure was erected by the Keystone Bridge Company, and an indication of the amount of work performed is furnished by the fact that its cost, excluding approaches, was $2,234,655.42. The masonry, including abutments, piers, tools, and machinery, was $2,364,452.26. This was one of the first of American bridges in which steel was extensively used. The supporting members of the superstructure consisted of 24 steel arches, 8 in each span. Each arch is composed of a large number of straight tubes, with slightly beveled ends, and to the casual observer appears to be a continuous curved tube. The whole number of tubes is 1,036. A tube is about 12 feet long, and comprises a steel envelope 1/4 inch thick, and 6 rolled steel staves, varying in thickness from 21/2 inches at the springing to 1 3/10 inches at the crown. The exterior diameter is always 18 inches. Steel or wrought iron sleeve couplings firmly unite the tubes by means of parallel grooves turned on the ends of the staves. About 2,200 tons of steel and 3,400 tons of iron are used in the whole bridge. The upper roadway of the bridge is 54 feet wide. The public test of the bridge consisted of placing fourteen locomotives simultaneously upon the tracks of a single span. The construction of the bridge was commenced during the seventh decade, and it was publicly opened on July 4th 1874.
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