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ward, scale 1 inch to 1 mile. A plat of the triangulation of 1891 was made. Additional sheets, 11 in number, of the 1:20,000 charts were published, making 81 sheets in all which have now been published, covering the river from Donaldsonville, La., to just below St. Louis, Mo. Recomputation of discharge measurements made in 1891 was completed. The daily records of the gauges kept by the commission, and of certain others kept under Majs. Mackenzie and Miller, Capts. Willard and Taber, of the Corps of Engineers, and under the Weather Bureau and the Cincinnati waterworks, were received, tabulated, and printed. The record includes 32 gauges at various points upon the Mississippi, from Hastings, Minn., to Fort Jackson, La., and 23 gauges upon tributaries and 3 upon the Atchafalaya. For further details, see report of Capt Carl F. Palfrey, secretary of the commission. (Appendix 4.)

GENERAL SERVICE.

The "general service" was originally established with headquarters at St. Louis for the purpose of furnishing to the various districts such supplies as could not be procured within the limits of the districts and could not be conveniently obtained by the officers in charge of the districts by direct purchase. As the work advanced and markets were developed the duties of this branch of the organization were gradually restricted, until of late years they have been limited almost exclusively to supplying stone from the upper part of the valley to the first, second, and third districts. For several years past the office has been in the same building with that of surveys, gauges, and observations, and has been managed by the same officer, the secretary of the commission. At the end of the year the "general service" was discontinued.

There were shipped to the first and third districts 40,208 cubic yards of stone. Loaded at the quarry ready for shipment on May 31 were about 3,500 cubic yards more.

Necessary repairs were made to the fleet. All of the vessels are in serviceable condition except the steamer Etheridge, which is deficient in boiler power. A large number of the stone barges will probably require very extensive repairs before the end of another year.

COMMERCIAL STATISTICS.

An attempt to collect commercial statistics for the calendar year 1891 resulted in procuring some incomplete information upon the subject, which will be found in the reports of the secretary and the officer in charge of the first district.

FIRST DISTRICT.

(Cairo to foot of Island No 40, 220 miles.)

(a) Columbus, Ky., 21 miles below Cairo.-The work of improvement at this locality consists of five spur dikes, built in 1889-290, under specific appropriations in the acts of 1886 and 1888 amounting together to $43,750, the object being to protect about 2,200 linear feet of bank which was threatening to cave. The work was completed last year. No injury to the spurs has been noted and no further work is at present required.

(b) Hickman, Ky., 36 miles below Cairo.-The acts of 1886 and 1888 contained specific appropriations for this locality, amounting together to $88,750. The evil to be remedied was the caving of the bank in front

of the town. Owing to the existence of a projecting point of tough clay a short distance above the landing it was possible to accomplish the desired result with an unusually small development of work. A continuous revetment about 1,000 feet long, extending down stream from the clay point, was placed in October, 1890. Except for some slight damages by an eddy at the downstream end it remains in good condition, but requires additional stone ballast. The stone for this purpose has been stored near at hand and will be distributed over the revetment during the next low-water period. Above the clay point the caving continues, but there appears to be no public interest which is suffering sufficiently to justify the large expenditure, estimated at about $160,000, which would be required to protect that portion of the bank. Should the clay point finally yield, then additional expenditures will be required to maintain the work now in place.

(c) New Madrid, Missouri, 71 miles below Cairo.-To comply with the requirements of the act of September 19, 1890, as interpreted by the War Department, an allotment of $1,000 was made to this locality from the appropriation contained in that act, as reported last year, to be used in making a survey. The survey was made in September and October, 1891. There has been some caving of the bank in front of the town, which the inhabitants desire to have stopped. The cost of protecting the bank is estimated to be about $70,000. The commission is unable to recommend the diversion of any of the funds appropriated for the general improvement of the river to this purpose at this time.

(d) Plum Point Reach, 147–186 miles below Cairo.-The works thus far undertaken in this reach, arranged geographically, beginning at the upstream end, are: (1) Daniels Point revetment; (2) Ashport Bend revetment; (3) Gold Dust dikes; (4) Fletcher Bend revetment; (5) Dikes in chutes of Elmot Island and Island 30; (6) Plumb Point revetment; (7) Plum Point dikes; (8) Osceola Bar revetment; (9) Bullerton revet ment; (10) Osceola and Bullerton dikes. They are distributed over a length of about 20 miles, some on one side and some on the other side of the river. They constitute one connected whole, each one being essential to the effectiveness of the others. The continued efficiency of all is dependent upon the maintenance of the conditions as to approach of the river from above which obtained when they were planned.

The order in which they were begun is different from the one just given, the object being first to obtain the desired results in the shape of a deepened channel and improved navigation, and then to maintain those results by repairs and extensions of the works themselves, and by the addition of such new works, higher upstream, as might become necessary. Thus the latest addition to the works is the one mentioned first on the above list.

(d 1) Daniels Point revetment.-Rapid caving having developed in the long bend known as Canadian Reach, of which Daniels Point is the foot, and there not being sufficient funds to undertake the protection of the entire bend when the appropriation of 1888 became available, it was determined to protect about a mile of the downstream end. As heretofore reported, a continuous revetment 5,300 feet long was placed. As a whole it has stood well, but the bend above it has continued tỏ cave, giving to the upstream end of the revetment a salient position. It has suffered some damage at this point. An extension upstream 500 or 600 feet was required, and was contemplated this year. There was also a small break about 400 feet below the upstream end, and additional stone ballast was required over a considerable portion of the old work. Owing to the difficulty of procuring stone, it was found impos

sible to do all the work required this year. The break was repaired and additional ballast was placed, but the upstream extension had to be deferred.

(d 2) Ashport Bend revetment. The protection of Ashport Bend was one of the first works projected in this reach. A short piece of revetment was placed in 1882, but more pressing demands for funds at other places prevented a continuation of the work until the present year. The bank had by this time receded so far that its protection had become imperative to avoid an injurious change in the action of all the works in Plum Point Reach. Operations were begun October 1 and continued until the middle of January, when they were suspended, having been greatly impeded by want of a sufficient supply of stone. Beginning at a point about 3,500 feet below Ashport, a continuous revetment was placed for a distance of 3,250 feet. It is proposed to continue the work during the coming year and to carry it to completion as soon as circumstances will permit.

(d 3) Gold Dust dikes.-No work done here and none contemplated. (See Annual Report for 1891.)

(d 4) Fletchers Bend revetment.-The protection of this bend was begun in 1884 and suspended in January, 1885, in an unfinished condition. Owing to restrictions contained in the act of 1886, by which expenditure of the funds appropriated in that act was prohibited for works of bank protection, this work could not be resumed until the autumn of 1888. It had then suffered some damage, but the most serious result of the suspension was the change in the form of the bend. Unprotected parts had caved back, leaving protected parts in a salient, and making the shape of the bend so awkward that it was deemed expedient to sacrifice the work protecting one of these salients. At the beginning of the present year the protection consisted of one piece of continuous revetment 7,800 feet long, beginning at the upstream end of the bend, then an interval about 4,000 feet long of unprotected bank, and of four detached blocks of revetment, each about 1,100 feet long, near the downstream end of the bend. The latter were separated from each other by intervals of 300, 400, and 500 feet, having been constructed in that manner as an experiment. The work this year consisted in extending the continuous revetment downstream to connect with the first of the detached blocks. Operations were begun in August and continued until February, when the project for the season was completed, except that the necessary quantity of stone could not be procured, and further ballasting remains to be done. Repairs also were made in the old work where needed. The indications now are that the interval between the two detached blocks of experimental revetment which are farthest downstream must be protected in order to save both pieces from destruction.

(d 5) Dikes in chutes of Elmot Island and Island 30.-Nothing was done to the original pile dikes and nothing is contemplated. (See Annual Report for 1891.) To complete the closure of the chute behind Elmot Island a submergeable dam of brush and stone has been projected and will be constructed as soon as circumstances permit. Some heavy masses of drift which accumulated against the remains of these dikes were sunk to aid in obstructing the flow through the chute. Compact mattresses of brush were placed over the drift and were then heavily ballasted with stone.

(d 6) Plum Point revetment.-Nothing done here during the year and nothing contemplated during the coming year. (See Annual Report for 1891.)

(d7) Plum Point dikes.-Nothing done here during the year and nothing contemplated during the coming year. (See Annual Report for 1891.)

(d 8) Osceola Bar revetment.-Rapid-caving of the channel face of Osceola Bar, or Towhead, having begun, a continuous revetment of brush and stone was begun last year. It was continued this year. At the beginning of the year the revetment extended from the downstream end of the Towhead a distance of 4,500 feet upstream. Operations were resumed in October and continued until the latter part of November. The revetment was extended about 1,000 feet farther upstream, and was there terminated, any further extension being for the present unnecessary. The supply of stone being insufficient, the work was not carried as high up the face of the bank as is contemplated. Further ballasting is required here.

(d 9) Bullerton revetment.-Nothing was done here during the year and nothing is contemplated for the coming year. (See Annual Report for 1891.)

(d 10) Osceola and Bullerton dikes.-Nothing was done here during the year and nothing is contemplated for the coming year. (See Annual Report for 1891.)

Results in Plum Point Reach.-The river reached an unusually low stage during the months of October and November, though the minimum gauge reading at Fulton, Tenn., was not as low as in 1887, 1888, or 1889, and at Memphis it was not as low as in 1871, 1872, and 1888. A discharge of only 91,000 cubic feet per second was measured at Memphis, October 16, with the gauge 0.4 higher than the minimum, which it subsequently reached. The least depth found in the improved part of the reach was 62 feet. It was found in the crossing between Gold Dust and Ashport Bar. Diminished depths were found in some of the other crossings. They are to be attributed to the large amount of channelchoking material thrown into the river by the caving of the banks, such as in Ashport and Fletchers bends, the protection of which had not been completed. The favorable results heretofore reported were not therefore fully maintained.

(e) Surveys, gauges, and observations.-Discharge observations were made at Cairo and Plum Point during the low-water period of 1891, and at Columbus, Ky., and Fulton, Tenn., during the high-water period of 1892. A hydrographic survey was made of the Plum Point Reach. survey was made of Hickman Harbor in October. The survey at New Madrid has already been mentioned.

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(f) Levees.-The only levees constructed by the United States in the first district are the two short detached pieces in the vicinity of the Plum Point Reach, built in 1886-'88. Nothing was done to them during the year. (See Annual Report for 1891.) There is no general system of levee maintained by local authorities within the limits of this district.

For details of the operations in the first district, see report of Capt. S. W. Roessler, hereto appended (Appendix 5).

SECOND DISTRICT.

(Foot of Island No. 40 to mouth of White River, 180 miles.)

(a) Memphis, 230 miles below Cairo.-Works for the protection of the harbor at Memphis include the protection of the city front, and of Hopefield Bend, above and on the opposite side of the river. The latter

work was begun in 1882, but for the reasons given in former reports it could not be completed until February, 1889. By that time the downstream end of the bend had receded so far that the approach of the river to the Memphis landing was no longer favorable to the maintenance of the upstream portion of the landing. A bar had formed here in front of the landing, where there are some important business interests, such as the grain elevator and railway transfer. During the low-water season of 1891 a channel was dredged through this bar, as in previous years, and there was no interruption of steamboat traffic to the elevator.

The damage to the revetment of Hopefield Bend, noted in the last Annual Report as having been inflicted by the high water of 1891, proved to be more serious than was then supposed. After the river had fallen two breaks were discovered, one about 2,750 feet long at the head of the 1884 work; the other about 600 feet long in the 1887 work and just above the repair work of 1890. The necessary repairs were begun in September and completed in January. Besides restoring the revetment at the places just referred to, additional stone ballast was placed where it was deficient at other places. During the present high water there have been two new breaks, one of them in the new work placed this year. The extent of these breaks is not accurately known, but appears to be moderate. It is proposed to repair them during the coming season. The protection of the city front was begun in 1878, before the organization of the Commission, at the upstream end of the landing. With the changes in Hopefield Bend the point of attack has moved downstream and the protection has from time to time been extended in that direction. The most recent work is the system of spur dikes, known as the "Citizen's Protection," originally built in 1886 with funds subscribed by property owners in the vicinity, the work being executed under the direction of the officer in charge of the district with plant belonging to the United States. They were raised and covered with stone by the Commission in 1889. They, as well as the revetments higher upstream, remain in serviceable condition, but there has been a decided settlement of the dikes. After the high water of 1891 a subsidence amounting to about 4 feet vertical was noted, but without lateral movement towards the channel. Caving continues slowly along the bluff further downstream.

(b) Helena, 306 miles below Cairo.-Nothing was done here during the year. See Annual Report of 1891.

(c) Surveys, gauges and observations.-Discharge observations were made at Memphis and Helena during the low-water period of 1891, and at Helena during the high water of 1892. A survey was made of Memphis Harbor in October, and one of Nonconnah Rock in the same month. The report of the latter survey is hereto appended. A survey was made also for a new levee behind Lake Charles (357 L), as the caving at the head of the lake and below it in the vicinity of Andersons Landing and Pushmataha has approached so close to the existing levee that new and extensive loops will be necessary or a new levee behind the lake.

(d) Levees. The levees in the second district include on the right bank the White River front, which extends from Helena to and including Laconia Circle, a distance of about 78 miles by river, and on the left bank so much of the Yazoo front as lies within its limits, a distance by river of about 120 miles. The lengths of levee are much shorter than these distances. Work was carried on during the year to a small extent upon both fronts.

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