This canal (according to its present plan) was projected by Col. T. J. Cram, of the Corps of Engineers, in August, 1866, as the best method of improving navigation at the mouth of the St. Clair river. He proposed opening the lower tortuous reach of the south channel, and making a direct cut from its mouth proper to deep water in Lake St. Clair. His project was approved, and construction began on the 20th of August, 1867, under contract with Mr. John Brown of Thorold, Canada. The original plan was a straight canal 300 feet wide in the clear, and 13 feet deep at low stage of water, protected by dykes 5 feet in height and 58 feet wide on top, built of the material dredged from the channel and thrown behind a pile and timber revetment. The canal was completed in the autumn of 1871, and turned over to the charge of Maj. O. M. Poe, Corps of Engineers, on the 11th of December. As completed, the banks are 7,221 feet in length, and constructed mostly of dredged sand thrown behind a revetment consisting of piling in two rows driven 13 feet apart and parallel, and capped with a timber superstructure 5 feet high, the front row being supplemented with a single row of sheath-piling to prevent the sand bank from washing back into the canal. As originally planned, the reverse faces of the embankment were to be permitted to take their natural slope, but as it was found that the banks if left so would be gradually washed away, they were secured eventually by a pile and plank revetment. The timbers in the superstructure were carbolized to prevent rotting, but the process proved a disastrous failure, owing to its imperfect application, and the timbers thus treated are as a general rule at this date a mere shell with a core of dry rot. The banks were planted with willows and sodded in some places. The history of the work since Major Poe took charge, excepting as regards the deepening of the channel for 200 feet of its width to a depth of 16 feet, as projected by that officer, has been a monotonous routine of stopping leaks on the canal face, due to the imperfection of the single row of sheath-piling, which permits the sand to be sucked through by passing vessels, and propeller-wheels working near the revetment. These leaks have been stopped from time to time at various points by various devices, such as marsh sod, etc.... The deepening of the canal was begun under Major Poe's direction by contract with Mr. John Brown of Thorold, Canada, in June, 1873, and finished September 23, 1878, under the direction of Major Weitzel, who had in the meanwhile relieved Major Poe. [Illustration: THE SHIP-CANAL AT THE ST. CLAIR FLATS.]