Mr. RAMSEY. The honorable Senfrom Missouri, [Mu HnxnsasoN] when this bill was before the Senate some days ago, expressed some surprise that I should advocate the building of bridges ii on the Mississippi river. That Senator should have known that at this time, without any authority of law, at least on the part of Congress, there are 2 bridges upon the Mississippi river which are alleged to be by those who trade upon that river the navigation interests there highly obstructive to navigation. There are but 3 bridges, I think, on the Mississippi river from the falls of StAnthon to the mouth of that stream. One is at Staul. That is a bridge of continuous span. It presents no obstruction to navigation. The bridge is elevated nearly 100 feet above the ordinary stage of water, and boats of the largest class that navigate the waters of that region pass under it without obstruction and without difficulty. There are 2 other bridges spanning the mississippi river, one at Clinton and another at Roe Island, both alleged to be highly obstructive to navigation, and bridges t iat have been remonstrated against by that interest for years past. So high has been the excitement at times that the boatmen following the river have been upon the point of abating the RockIsland bridge as a nuisance by violence. The remonstrance s were so strong against its continuance that in 1859 a commission of Officers of the Topographical corps of the U.S. lair any was appointed to visit and examine that rige. " The engineers of the railroad companies and the river interests differ entirely as to the character of the bridges that should be erected across the Mississippi river. Those having charge of that interest at StLouis the Chamber of Commerce claim that the span upon the pivot bridges should be 400 feet. On the other hand it is alleged by experienced engineers that a span of that size would be much more obstructive than one of a reason able size; that the ditheulties of opening it at times would be such as unfavorably to obstruct navigation upon that river. The commission which was sent by the SecyWar in 1859 to examine the RockIsland bridge was composed of Captain Hum phreys, Captain Meade, and Captain Frank in, of the Topographical corps, each of whom has since attained tnc position of major general in the Army. In their report upon that ocea sio"n they said: From the drawings above alluded to and from personalexamination, the board found that the railroad bridge is placedat the foot of the rapids, and is thrown from the island of Hock Island to the city of Davenport, Iowa; that it is supported by twostone abutments on the shores and 6 stone piers. The spans(live in number)“1:0250 feet. broad.the draw spansbein at the water level (9 and 1/2 feetstage) on 107 mteaeknianngd 112 feet respectively. the whole length of the bridge 1535 fer t. “The piers. except thoseof the draws. are 35 feet long and 7 feetbroad at top and 53 feet long and 11 feet broad at the bottom. Thotwo smalldraw piersare 38 footlongand ton feet broad at top and 34 foot long and ifnoculrutdeienngbroad at the bottom. The tap table pier. the guard pier and sterling is 355 feation and 40 and 1/3rd feet broad iit the top and 386 feet long 45 feetbroadat the bottom This pier is composedof a stone center pier 35 feet Indiameter at the top. the remainder being crib work filled with stone. Ilic lllt rllLltDIstarlings of all the piors are isose eles right iniialed triangles. the center line of the roadway crosses the t.nmtablo pier 210 feet.from its head.this piercing 15 feet loug and 19 feetwider on the top than the trusswhich forms the dpraatwen.t The superstructure of wopd.built uponllowon is 20 feet aboveordinary high and 33 feet aboveordinary low water." The great vice in that bridge is the of the piers to the current of the riveor.bliq Flhtiys commission further state: It will be seenthat above the byidge the direction of the current makeswith the IX]! of the piers. dif foront angles varyin from 23o to 14o30; that through the Illinois draw of the bridge. the angle with c axis of the pier is 5o and that below the bridge the angle varies from 8o to 9o30!" Were the same piers placed parallel to the current the obstruction tot cjlow of the water would be about 1/3rd of what it now is.“ The general level of the river its raisedby the is: of the bridge.40feet, or nparl 6 inches, an the increaseof the mean velocity no to the contraction of the water way is 2.27feet per2nd or 1.55mils: per hour, making the computed velocity under the bridge 5.55miles perhour. "In summing up their conclusions, they say: 1. The board isof opinion that the railroad bridge which crosses the Mississippi river between RockIsland. in the state of Illinois and Davenport. in the State of Iowa, is not constructed according to correct principles, reference bun: had to the interuta of naviaation. "2. The piers of the said bridge are not of the best form and that there was no practical difficulty in constructing them of the proper form. “ith the onetion of the turn table pier, thp board isof opinion that the defectivetermof the men; is a matter of no material importance. The turn table plor will be moreparttcu arly rater redto in the insurer to the nextquestion. “3. heonly pierlarger thanis necessaryistheturn table or. This pier. in the opinion of the board, should have been constructedno longer or broader than was absolutely necessary to sustain the truss when the draw is o en and protect it from new by passing boats. t might have been constructed with a length of 295 fact. afforiling ample support and rotcction. pnd being actually 355 feet in length: the dificrcuco, 60 feet, is unpecessary and in the judgment.of the card. pernicious. Thaetfeqt of making it longer than was absolutely required, is to contract the waterway increase the reocity. nar row the draw passage and present more surface for boats tostrike aglainstthus inercasing the difficult y of their assagct rough the drn w. In a pier of this sizethe form of the starlingis of importance and the upperfacesof the pier should have beencurvedlllll aces. 4. The lpiersarenot placed parallel tothocurrent, but at um: 98varying from 26oto 14o80. The effect of this obliquity is to treble the obstruction to the flow of the water and consequentlyto infect the increaseofveloci in the same ratio. Another conne uenes is that the passagesof steamboatsand rafts t rough the draw and betweenthepiersare rendered much more difficult and hazardous. Furthermore. the draw on the Iowa side is rendered useless by the formation of an eddy therein. “ 5. The velocities of tho differcut partsof the river in the yicinity of the bndgo have already been Id, and will be found tabiilated in appendix C. “6. The eddy on the Ioyvaside otcturn tablepiizr asnearly as could be estimated is about 100 feetwide at the foot of the icr and the turbulence orboilin of the water exten sabout 500 feet below, his eddy.however.is constantlyvaryingin imposition and dimensions. Its shoot on the passes:ss of cats ase endingand dese endingis undoubtedlyto render them more difficult, on account of the czre requiredto avoid getting one part of the boat in it while another part is in the current of the draw. It has beenpreviouslystated thatthe effect of thuediy in the Iowa draw is t to render it uselcm.” "In conclusion. the board consider! it proor to recapitulate some of the well known prinnciples of brid O building, to show how far they have bein cop orined to or departed from in the Rock Isla ad bridge. These principles are: “1. That at a RlVOIlplace, in locatingo bridgeoi er any strcamdho site where the velocity of the cum at is a minimu should beselected. "2. That in csigningabndgc. the picrsshouldhs rea minimum cross suctionconsistentWiththe suppitrt of the snperstructurcthuse ffernig the least obstriction to the flow of the water and inc reusingthere O city of the current as little as possible. 3. The piers shculd alwn sbeplacedparallcltot he thread of the stream, for esame reasons asthise statedin the 2nd principle and because tl icytlas re“nder the passageof boatsand rafts lossdilhcult. 4. In designing a bridge overariver haying aliu Be commercein boats and rafts,the draws and sptas sh"ould be of the greatest practicablewidth. In a plying these principles to the Rock Isla did bridge. the card is constrained. vnth extreme rug; 2!. to report that iill have beenviolated; thus renderiis the bridge not.only an obstruction to the nannti in of the river. but one materially greater than there was any occasion for. “The board fully appreciates the value and importance of the railroad traffic, and is of opinion bridge that a is necessary and should lip constructed. not only at RockIsland, but at other points on the Mississippi river; but.it is also of opinion that the interests involved in the free navigation of this noble stream demand that in locating and constructing these bridges unusual study should be brought. to bear to insure the presentational"the least pouiblo obstruction to the navigation, and that all considerations of expediency and economyshould be madeto yield to the paramount interestsof the commerceof the river." The ComPostOffices, to whom this bill was referred, sought information on the subject from every source where they could find it. The bill as referred to them provided for a draw of but 300 feet, leaving a clear draw on either side of the pivot pier of less than 150 feet, probably not over 110 feet. It was also mandatory on the company to build a draw bridge. Inasmuch as the committee conceived that a bridge of continu ous spans was to be greatly preferred to a draw bridge, they chaned the bill in that respect, ieaving it optioua with the company which to build. The Senfrom Missourisaid that there was no use in referring these bills to that committee. that they would make no examination or modification of the m, but simply report them as they received them. If he had read the bill as reported by the committee, and also the bill as referred to them, he would have seen that the have made very important modifications, an all in the interestsof the navigation. We have provided in the bill as reported that the draw shall be 350 feet, leaving a clear passage on either side of the pivot pier of 150 feet. If the bridge shall be built with unbroken and continuous spans, it is to be 50 feet above extreme high water. This, we learn from exerienced river men, is all that is desired. I ere the chim nies are taller than that, the arrangementis to lower thern upon the telese opic plan which has been introduced there. With renrd to the spans other than the pivot span, we have the information of competent epgineers that an excess of over 300 are is not advisable. General McCalluin, who had charge of railroad and bridge structures during the war, says:, "The longest draw bridge ever constructedin this country i. of 2 openingsof 150 feet each. although I do not consider even ii.greater length than this impracticable. Ineverthelcss would consider it unnecessary and impolitie. Any bridge located at right.angleswith the stream.with current of not more than 4 miles perhour. all purposesof navigation should befully met by 150 feet openings.”