front of Arkansas City, placing 19,235 cubic yards. The Chicot County levee board constructed levees at Luna (467 R), Leland (483 R), and enlarged those at Bellevue front (466 R) and at Sterling (515 R), the yardage not being reported to the Commission. The Louisiana authorities, compelled for their own protection to go beyond the limits of their State, enlarged the levee from Chicot (432 R) to Arkansas City, placing 148,638 cubic yards. They also contributed 45,611 cubic yards to the Lucca loop (428 R), built mainly by the United States.

(h 2) Tensas Basin, Louisiana, third district.-With this year's allotment for this subdistrict a levee was built at Illawara (562 R), containing 349,241 cubic yards.

For details of the operations in the third district see report of Capt. C. McD. Townsend, hereto appended, Appendix 6.

FOURTH DISTRICT.

(Warrenton, Miss., to Head of Passes, 484 miles.)

(a) Natchez and Vidalia, 700 miles below Cairo.-A history of Congres sional and executive action with reference to this locality was given in the last Annual Report. Nothing was done here during the year.

(b) Rectification of the Red and Atchafalaya rivers, 764 miles below Cairo. The project adopted for this locality has for its object (1) to limit the outlet capacity of the Atchafalaya, and (2) to improve the lowwater navigation from the Mississippi into the Atchafalaya, and also into the Red River.

The first of these objects is to be accomplished by the construction of a series of dams in the Atchafalaya, submerged sufficiently to permit navigation over them. At the date of the last Annual Report two of the projected dams, Nos. 1 and 3, built in 1888 and 1889, had been constructed near Simmesport, in the Atchafalaya, about 5 miles below its head. They remain in good condition. Nothing further was done here during the year.

The second object is to be accomplished by replacing the present single channel between the Mississippi and the Red-Atchafalaya, through which the flow is sometimes in one direction, sometimes in the other, and sometimes does not exist at all, by two channels, one for the inflow from the Red to the Mississippi, and the other for the outflow from the Mississippi to the Atchafalaya, and to prevent the Red River, at low water, from wasting itself down the Atchafalaya, by a dam which shall separate it from that stream at low and medium stages. One of these channels is furnished by the present single channel, called Lower Old River, south of Turnbull Island. The other is to be created by the enlargement of Upper Old River, north of Turnbull Island, for the greater part of its length, until it reaches the vicinity of Carrs Point, and then continuing it to a junction with the Mississippi by excavation through Carrs Point.

The difficult part of this project is the excavation of the channel north of Turnbull Island. The old waterway has much diminished in size in the last few years until now a narrow chute, which is dry in places at a 12-foot stage, is all that remains of it. Several million cubic yards of material must be removed. The material is soft mud, in which a trench is difficult to maintain, the semifluid sides flowing into it with great facility. A small amount of dredging was done last year, as noted in the last Annual Report, and operations of that kind were resumed in the early part of the present year; but a very brief experience was sufficient to demonstrate that the appliances at the disposal of the Commission were not adapted to the circumstances of this case. ENG 92-182

Dredges of much greater capacity were required. Operations were promptly suspended, and an investigation of the resources of the country in dredging appliances was entered upon, with a view to procuring the most efficient one for this purpose which exists or can be constructed. Specifications were finally prepared, and proposals for furnishing an efficient apparatus were invited by public advertisement dated June 1, proposals to be opened on the 1st of August next. To aid in the excavation of this channel it is very desirable that a current from Red River be forced through it as soon as practicable. This could be accomplished by building to a sufficient height the dam designed to separate the Red River from the Atchafalaya, known in this project as the Red River Dam. But the Commission did not feel at liberty to obstruct the navigation which now passes over the site of that dam before providing a new channel. The dam was begun in 1889 and at the beginning of the present year it had been built up until its crest was from about 1 to 3 feet below low water. It was the intention up to the time when dredging in Upper Old River was suspended to continue the construction of the dam to a moderate height above low water, so as to obtain some assistance from it if possible in the way of a current through the new channel, but at the same time to keep it so low that in case of a very low-water season a portion of it could be cut down, and a channel through it preserved, without too great a loss of material. The work of construction was continued in the early part of the present year. When dredging was suspended orders were given to suspend work upon the dam also, as soon as convenient, but to use up such material as had been accumulated. Its crest when work was suspended was about 3 feet above low water. The river subsequently fell to a very low stage and a portion of the dam was removed in compliance with orders given before it was built, in anticipation of such a contingency. There is now an opening through it about 450 feet wide and 5 feet deep at low water. Otherwise it is in good condition.

It is evident that the execution of this project is much hampered by the necessity of not obstructing the use of the stream by navigation. The navigation interest has this spring very generously come to the aid of the Commission. In a communication signed by all, or nearly all, the masters, owners, mates, and pilots of boats engaged in trade to the Atchafalaya, Red, and Ouachita rivers, they have urged that the approved project be pushed to completion, that the Red River Dam be raised so as to force the Red River to flow north of Turnbull Island and of itself create that channel, and have voluntarily offered to relinquish the use of the old channel thus obstructed. The Commission has not thought it best to accept this offer at this time, believing that both dredging and a current are necessary. It is proposed to resume operations when a satisfactory dredging outfit is secured, and sufficient funds are available, and then to take advantage of this offer.

The usual difficulties were experienced in maintaining a navigable channel through Lower Old River during the low-water period. Dredg ing was begun as soon as the water had fallen sufficiently to permit the dredges to work and was continued until the water was too low to float them. By October 6 the channel had become impassable for the regular steamboats, though small light draft boats continued to go through and transfer freight until October 30. At that time all navigation was suspended and it so remained until November 27, when both the Red and the Mississippi rose rapidly and navigation was restored. The telephone line, 30 miles long, to connect with West Melville, the nearest railway station, the construction of which was begun last year, was completed.

(c) New Orleans Harbor, 963 miles below Cairo.-The city of New Orleans covers a length of about 13 miles of the Mississippi River. In that distance the river makes four bends, called the Carrollton, Greenville, Gouldsboro, and Third District bends. In all of them more or less erosion was going on, which, as the value of property increased, it became desirable to stop. The features of the case, which are peculiar. and make it different from other places where the protection of banks has been undertaken, are (1) the great depth of water and steepness of the banks, which are unfavorable, and (2) the comparative stability of the banks, which has enabled New Orleans to occupy essentially her present site for a century and a half, which is favorable. The system of spur dikes was introduced in 1884, and has since been used exclusively, and has thus far been successful. The spurs begin near the lowwater line and project into the river to the point where their_top surfaces, having a slope of 1 upon 3, intersect the bottom. They are usually about 1,000 feet apart, but the interval may vary with the greater or less curvature of the bend.

At the beginning of the present year there had been placed in New Orleans Harbor 3 spurs in the Carrollton Bend, 2 in the Greenville Bend, 6 in the Gouldsboro Bend, and 4 in the Third District Reach, a little below the bend. During the year 4 additional spurs were built in the Third District Reach and 2 in the Carrollton Bend. They were all in good condition at the end of the year, and appear to be accomplishing the object for which they were designed. The construction of additional spurs is contemplated.

(d) Surveys, gauges, and observations.-Discharge observations during the low water of 1891 were made in the Mississippi at Red River Landing, in the Atchafalaya near Simmesport, and in the Red River at the Red River Dam, and during the high water of 1892 in the Mississippi at Natchez, Red River Landing, and Carrollton, and in the Atchafalaya at Simmesport. Local surveys were made in the vicinity of Red River Dam and at five places in New Orleans Harbor, and in connection with the location of new levees, and a continuous line of levels was run over the levees of the Tensas Front from the upper end of the district down to Fairview Landing.

(e) Levees.-The levees in this district include the lower half of the Tensas Basin and the Atchafalaya Basin on the right or west bank, a distance by river of about 432 miles, and on the left or east bank, the low country below Baton Rouge, a distance by river of about 206 miles. The local organizations for the right bank are (1) Fifth Louisiana levee district, extending from the State line to the mouth of Red River, (2) Atchafalaya Basin levee district, extending from the mouth of Red River to Donaldsonville, (3) Third Louisiana levee district, extending from Donaldsonville to the Gulf of Mexico, except about 13 miles at New Orleans. Those for the left bank are (1) Pontchartrain levee district, extending from Baton Rouge to the upper limit of the city of New Orleans, and (2) First Louisiana levee district, extending from the lower limit of the city of New Orleans to the Gulf of Mexico. The Orleans levee district includes all levees on both banks within the limits of the city of New Orleans, extending about 13 miles on each bank. Allotments by the Commission have been made under the titles "Tensas Basin, Fourth district," "Right bank below Red River," and "Left bank below Red River."

(e 1) Tensas Basin, fourth district.-At the date of the last Annual Report the levee which had been begun at Gibsons Landing (683 R) was not completed. It was finished this year. The levee at Henderson (712 R), which had been contracted for last year, was built this

year. In addition to these the following lengths of levee were constructed, viz: 9,840 feet at Hardscrabble (639 R), 11, 632 feet at Kempe (659 R), and 136 feet at the Ferriday crevasse (693 R), containing in all 399,831 cubic yards. They were built with a crown of 8 feet, side slopes 1 upon 3, and to a height from 1 to 3 feet above high water of 1890. Work was done by the local authorities, the amount and location of which has not been reported to the Commission.

(e 2) Right bank below Red River.-After completing the levees which were reported as under way at the date of the last Annual Report, the following lengths of levee were constructed, viz: 600 feet at Nina (806 R), 8,021 feet extension at Highland (815 R), 4,743 feet at Mayflower (853 R), 3,686 feet at Fortville (855 R), 3,400 feet at Evergreen (857 R), and 783 feet at Dumboine (865 R), containing in all 435,550 cubic yards. They were built with a crown of 8 feet-except at Nina, where it was 6 feetside slopes of 1 upon 3, and to a height of from 1.2 to 3 feet above high water of 1890. Repairs were made to the levees in various places, removing weeds, replacing sods and restoring slopes damaged by rain wash. Work was done by the local authorities, the amount and location of which have not been reported to the Commission.

(e 3) Left bank below Red River.-In this subdistrict the following lengths of levee were constructed, viz: 9,258 feet at Southwood (extension) (875 L), 1,959 feet at Tessier-Bourgeois (909 L), and 1,372 feet at Southport (955 L), containing in all 165,911 cubic yards. They were built with crowns of 8 feet, slopes 1 upon 3, and to a height 24 to 3 feet above high water of 1890. Repairs were made at various places.

For details of the operations in the Fourth District, see report of First Lieut. John Millis, Appendix 7.

HIGH WATER OF 1892.

The high water of 1892, though of unusual height in the upper Mississippi-at St. Louis not having been equaled since 1858-was not of excessive height in the upper part of the main trunk below Cairo. As far down as Helena, 306 miles below Cairo, and for some distance below that, it has been exceeded half a dozen times in the last ten years. Below the Arkansas River it was the highest upon record. One of its remarkable features was the lateness of the season at which it occurred. In some cases the highest stages were not reached until after the date, May 27, at which the executive officers of the Commission rendered their annual reports. Later information seems to indicate that the maximum stage of the river has been passed, but at this writing, June 16, the water is still very high, having fallen but a few inches from the highest stage reached, referring always to the portion of the river below the Arkansas.

The information before the commission concerning the flood is at present incomplete. It seems probable that the maximum strain has been placed upon the levees which they will have to bear this year, and that but little, if any, further damage will be suffered by them. Only a very general view of what these damages are can now be given. The number of crevasses has been somewhat greater than the number last year, though insignificant compared with the number in former years of great floods. A large part of the Tensas basin in Arkansas is overflowed. There has been no break anywhere on the Yazoo front or on the Atchafalaya basin front or in the Orleans district. The local organizations in those districts had made more serious efforts to strengthen their levees than had the local organizations elsewhere. Crevasses have occurred in the Pontchartrain district and in the First

and Third Louisiana districts, but at this writing it is not known how extensive the overflow from them is. The district officers have been untiring in their efforts to hold the levees. Upon the approach of the flood the engineering staff was stationed at critical points, sacks and lumber were distributed, and steamers required for transportation and inspection were employed. In coöperation with the local authorities, the weakest levees have been under constant inspection and many repairs have been promptly made as required. That these efforts have not in all cases been successful should not be surprising. The levees require an expenditure of several million dollars to put them in a state of reasonable security against great floods. That they should yield in places during the highest flood heretofore recorded is to be taken as a matter of course.

LOW WATER OF 1891.

The stage of the river in October and November, 1891, though not the lowest upon record, was so low as to seriously obstruct commerce. Most of the steamboats and barges were laid up, and such as continued to run were compelled to carry greatly reduced loads. The large grain crop of this country and the great demand for it in Europe rendered this an unusually serious misfortune. Millions of bushels of wheat which had been sold in Europe were lying in the elevators of St. Louis, without means of transportation, while the grain barges were tied up at the bank. Urgent demands were made upon the commission for relief, by a temporary removal of the crests of the most prominent bars by dredging, and several devices for accomplishing that result, very easily as the designers supposed, were presented. The idea of procuring temporary relief to navigation during the low-water period at a small cost is a very attractive one and has at one time or another engaged the attention of probably every engineer, including the commission, who has been employed upon the river. It would seem at first glance to be a simple matter to shave off the crests of a few of the more prominent bars and thus materially increase the draft to which vessels may load. Long's scraper and the portable wing dam of Adkins and Keiser are among the devices to accomplish this object which have been built and tried and have failed, while those which have been designed and proposed are innumerable and of every description. The difficulty in applying successfully any of these devices lies in the great building power of the river, the inconstancy of its flow, and its great width. It is essential that the device, whatever it be, shall not oppose the tendency of the river, but shall aid it. In a river a mile or two wide, with perhaps several channels of equal dimensions, it will often be difficult to tell by casual observation which one of these channels it is tending to enlarge or abandon. The tendency one day may be reversed the next by a sudden rise or fall in the river's stage. Hence the commission has never been sanguine about the possibility of obtaining useful results from experiments with dredging appliances in the Mississippi. It condemns without hesitation all devices which rely exclusively upon the current of the river for carrying away the excavated material. However useful such devices may have proved upon small streams, upon bars of moderate dimensions, no good results can be expected of them in the Mississippi, where the distance across the bar is often a mile or more. Likewise, it condemns all appliances of small capacity, such as the dredges to be found in ordinary use. Where hundreds of thousands of yards of material must be moved, and moved promptly, some quicker and cheaper appliances than those are needed. In the judgment of the commission some dredge of great capacity, which can