2d. The conditions of its use are, that parties interested shall be at the expense of putting the boat in good order, making all required repairs, of keeping the boat in good order, and of using the boat. That the boat is not to be taken from the direction and control of the United States superintending engineer. That the plan of operations is to be the same as the plan recommended by the United States board of engineers, and as approved by the War Department, which has been communicated; of all which you will be more fully informed by the enclosed copies. It is considered proper that you should repair to Detroit, in order to consummatethese arrangements, making full report there of to this office. It is not considered necessary to submit the matter again, to the War Department, unless you should consider that any part of the proposed arrangement should be dispensed with or modified. Captain Macomb to whom the report and plan of the St. Clair flats was sent, is directed to hold them subject to your orders. Respectfully, sir, your obedient servant, J. J. ABERT, Colonel Corps Top. Eng. N 4. Colonel Abert to the Hon. Secretary of War. BUREAU OF TOPOGRAPHICAL ENGINEERS, Washington, September 22, 1854. SIR: I have the honor to acknowledge your direction to report upon a letter from the Hon. Lewis Cass of the 16th instant. This letter states that a "committee on behalf of persons interested in the navigation of these lakes," desire permission to use the United States dredge boat built for the purpose of deepening the channel over the St. Clair flats; that these persons are responsible; will do the work at their own expense, and will return the boat in good order. General Cass states "these applicants are business men of character and responsibility, and will make good all their assurances. I should have no hesitation, were it deemed necessary, to become their security for that purpose." no objection occurs to this office to loan the boat as desired upon the conditions that: 1st. The United States shall be at no expense for prepairing the boat for use, and for taking said boat to the locality of the flats. 2d. That the persons to whom said boat is loaned shall be responsible for her safety and shall return said boat in good order, when required. 3d. That the return of said boat shall not be required in less than forty days after said boat shall be received, but said persons, to whom the said boat shall be loaned shall be responsible for her safety and for her safe keeping, until required to return said boat, which latter period shall not exceed six months after said boat shall have been loaned. 4th. That the said boat shall be employed at the lake St. Clair flats, and on the improvement of such channel as shall be designated by the approved plan of the War Department. 5th. That if required the War Department shall send an officer to mark out the channel to be improved. The board of engineers upon lake harbors and western rivers has now in hand the proparation of a final report upon the improvement of the St. Clair flats, and the said board, having read this communication, authorizes me to say that it accords with this report. Respectfully, sir, your obedient servant, J. J. ABERT, Colonel Corps Top. Eng. Hon. JEFFERSON DAVIS, N 5. Indorsement on the above letter. Is it proposed by the chief topographical engineer to allow the boat to pass from under his control, or only to be employed under the supervision of such person as the government shall choose to put in charge of it, all expenses being provided for and a satisfactory security given against loss to the government? WAR DEPARTMENT, September 25, 1854. JEFF'N DAVIS, Secretary of War. N 6. Colonel Abert to the Secretary of War. BUREAU OF TOPOGRAPHICAL ENGINEERS, SIR: I have the honor to acknowledge a reference to this office of the report of the 22d instant. On reading over the report from this office, I readily admit the necessity of the questions now put, and in order to remove all doubts, and as a substitute for any other plan, it is respectfully proposed that the "committee" referred to in the letter of General Cass be required only to raise requisite funds; to hold these funds subject to the control of such officer or agent as the War Department shall appoint; this officer or agent to expend said funds, and to use said boat, for the improvement of the St. Clair flats, in conformity with such plan as the War Department shall approve. The St. Clair flats work is under the general direction of Brevet Lieutenant Colonel Graham; but, considering his duties on Lake Michigan, it will, I think, be found advisable to have an officer or local agent in the immediate direction of the work on the flats. Respectfully, sir, your obedient servant, Hon. JEFFERSON DAVIS, J. J. ABERT, Colonel Corps Topographical Engineers. Secretary of War. N 7. Indorsement on the foregoing. Approved as recommended. The committee will be distinctly informed that no claim to refund the money expended, or for other indemnity on account thereof, is to be based on the acceptance of their proposition to use the United States dredge boat, at their expense, for the purpose of deepening the channel over the St. Clair Flats. JEFF'N DAVIS, WAR DEPARTMENT, October 4, 1854. Secretary of War. N 8. Colonel Abert to the Secretary of War, on submitting the final views of the board of engineers in regard to the St. Clair flats improvement. BUREAU OF TOPOGRAPHICAL ENGINEERS, SIR: I have the honor to submit the final views of the board of engineers (see N 9) in reference to the St. Clair flats. From these views it appears that to make a channel 300 feet wide (exclusive of cost of dredge boat) will require (A) $27,252; and that to make a channel 600 feet wide (exclusive of cost of dredge boat) will require (B) $59,563. In the estimates the board excludes the plan of protecting either or both sides of the artificial channel-way by crib work and sheet piling. It would be a fortunate event if some structure of this kind were not required. In my opinion it is essential and will be required; and, to avoid the evil of removing it in order to enlarge the channel at a future day, the work should, in the first instance, be applied only to one, the permanently fixed side. This consideration would probably add to the estimate for the 300 feet channel about $5,000, enlarging that estimate (A) to about $32,000. It is also probable (in my opinion) that this protecting work will be required before the dredging be commenced. Respectfully, sir, your obedient servant, J. J. ABERT, Colonel Corps of Topographical Engineers. Hon. JEFFERSON DAVIS, Secretary of War. N 9. Report of the board of engineers, to the chief topographical engineer, on the plan for improving the channel over St. Clair flats. OFFICE BOARD OF ENGINEERS FOR LAKE HARBORS AND WESTERN RIVERS, Washington, September 25, 1854. SIR: In relation to the question of improving St. Clair flats, Michgan, a subject recently referred to the board for consideration and a final report, I am instructed to make the following statement, viz: St. Clair river, at its outlet in St. Clair lake, forms a very extensive delta, occupying an area roughly estimated at 70 or 80 square miles. Within this area the river breaks into numerous branches and enters the lake very much reduced below its original velocity, Owing probably to this diminution of velocity, extensive shoals are found in front of the delta, and in these shoals are channels more or less useful for navigation, but obstructed by bars. The channel presumed to be most convenient for navigation is the south channel or pass, and its subordinate channels named on the charts. The western channel, the middle channel, and the eastern channel of the south pass. One of the questions in the present investigations is, which of these channels should be selected for improvement? The board, while engaged upon the estimates for lake harbors for the fiscal year ending June 30, 1855, had before it an item for the improvement of the uavigation of Lake St. Clair. It had before it also the report, plans, and estimates of Captain Canfield, late of the corps of topographical engineers, and for the reasons "adduced by Captain Canfield, it was c opinion that the middle channel (of the South Pass) should be adopted for improvement; and, moreover, that the lesser width (300 feet) recommended by him be first opened, and hereafter, should the operation prove successful, and the wants of trade call for a greater width. that it then be increased to at least 600 feet." Captain Canfield was of opinion that sheet piling should be employ ed for the protection of the sides of the proposed channel, and the board in its report admitted this amongst the items which it adopted. He makes, however, the following remarks bearing upon the subject of the composition of the shoals, and the probable permanency of the channels: "If it is borne in mind that the place is entirely out in the open lake more than a mile and a half from anything like shore, the fact will be apparent that there can be scarcely any perceptible current at that place, not sufficient in any degree to effect the bottom." He says, also, it is found by the survey of last fall that scarcely any change has taken place in the depth and form of the channel within the last ten years, when the first survey was made." These observations go to justify the opinion that the sides of an artificial channel would not probably require protection, if they were cut to the same slope as that which we already find standing in the natural channel. For these reasons the board is not prepared to advise the use of sheet piling, or of any other protection for the sides of the proposed channel in the first instance, more especially if it is to be opened at first upon a width of only 300 feet, with the prospect of enlarging it hereafter to a width of 600 feet or more, for it would savor of extravagance to establish lines of piles which must be necessarily removed as a preliminary to such enlargement, and it might be also objected, that in a few years the piles would decay to the surface of the water, and, being in the open lake would, in rough weather, be dangerous to vessels passing between them in the night. For these reasons, the board repeats the opinion, that the plank piling provided for in the estimate should not be used until experience shall have shown that they are necessary for the defence of the channel. It should be observed, that the lines traced in red upon the chart, indicating the proposed lines of improvement, are intended by the board to show only the general position and direction of the work. It is desirable that the first excavation should be made upon the lines the most convenient for the ultimate enlargement of the channel, which should proceed at the same time from both sides of the original cut, nearly on straight lines, these being the most convenient for vessels proceeding up and down the channel, especially at night. The depth of the channel should be twelve feet. Should the plank piling be omitted, there will be occasion for a greater number of channel marks than has been provided for in Captain Canfield's estimates. This, however, is presumed to be a subject within the province of the light-house board. The contemplated light-house should occupy the position selected by Captain Canfield, namely, at R. Its distance from the nearest light, at the head of Detroit river, is but about eighteen statute miles. The light, therefore, need not be of a superior order, nor very elevated. A Fresnell illuminating apparatus of the fourth order would be sufficient. It should illuminate the whole of the horizon. The beacon light should be the usual lantern employed by the light-house board for wharf lights. With the preceding modifications, the estimate for a channel three hundred feet wide at bottom, and twelve feet deep, with sloped sides of twenty feet one inch, would stand as follows, viz: |