248 



ENGINEERING. 



only with New York and the Sound ports, but 

 will render the coasting-trade speedier and safer 

 between New England and all the rest of the 

 seaboard. The tinal survey of the route was 

 made in July, and work was commenced the 

 middle of September, 1880. The northeast end 

 of the canal is about one third of a mile north 

 of Sandwich. Here two parallel jetties will be 

 carried out into deep water, forming a prolon- 

 gation of the canal-banks. An interior basin 

 of ten acres' area, made by excavating a salt 

 marsh within the line of the shore, will serve 

 as a harbor. It connects with the canal and 

 the channel between the jetties at their point 

 of meeting. Breakwaters will be so constructed 

 that vessels can run up into the basin from Cape 

 Cod Bay in all weathers. At the head of Buz- 

 zard's Bay and at the mouth of Monument River 

 is an excellent natural landlocked harbor. The 

 engineer employed by the same company in 

 1878, Clemens Herschel, estimated the cost of 

 the canal at $2,500,000, allowing only 15 to 20 

 cents per cubic foot for excavation, which esti- 

 mate was only one quarter of that first made by 

 the present engineers. The former schemes for 

 a canal over this route all contemplated a 

 greater or less number of locks. The bolder 

 plan of an expeditious, free channel cut below 

 the level of the tide was first adopted by the 

 company which has now taken this work in 

 hand, and is the result of the vogue for ocean - 

 level canals brought about by the great achieve- 

 ment of Lesseps and his still greater new enter- 

 prise. A serious drawbnck to a tide-level canal 

 across Cape Cod may be encountered in the 

 strong tidal current, which Herschel calculates 

 will run through at the rate of four knots an 

 hour. Navigation against such a current must 

 be attended by expense and delay. Whether 

 it would also injure the banks and bed of the 

 canal, or entail expensive works for their pres- 

 ervation, can not be clearly calculated before- 

 hand. In the second and third weeks of Sep- 

 tember several hundred Italian laborers were 

 set at work clearing the ground and commenc- 

 ing the excavation at Sagamore Hill. The Cape 

 Cod Ship-Canal Company was incorporated in 

 the year 1870, and would perhaps have com- 

 pleted the undertaking some years ago had it 

 not been for the financial panic of 1873 and its 

 effects. They were compelled by statute to ex- 

 pend $100,000 on the canal and collect $400,- 

 000 into their treasury before the 1st of Novem- 

 ber, 1880, or to forfeit their charter. A second 

 company was chartered April 24, 1880, who 

 should succeed to the privileges of the old one 

 in default of their fulfilling these conditions. 



The route of the ship-canal which it is pro- 

 posed to dig across the peninsula of Florida 

 has been surveyed under the direction of Gen- 

 eral Q. A. Gillmore. If constructed, this canal 

 will effect a saving in distance between Atlan- 

 tic and Gulf ports of about five hundred miles, 

 besides the escape from the perils of the pas- 

 sage through the Florida Straits. The route 

 recommended starts from the St. Mary's River 



on the east, and descends to the Gulf of Mexico 

 through San Pedro Bay. Its length from the 

 bar opposite the mouth of the St. Mary's to 

 deep water in the Gulf is 169 miles. From the 

 bar to the mouth of the river the distance is 

 5^ miles. There are 34 miles of ship naviga- 

 tion in the St. Mary's to Camp Pinckney, the 

 eastern terminus of the canal proper. The 

 length of canal to be excavated from here to 

 Ellaville is 122 miles, and from this point to 

 deep water in the Gulf 7i miles. The summit- 

 level is 105 feet above tide- water. The plan is 

 to ascend the St. Mary's River to the summit- 

 level by means of seven locks of 15-feet lift each. 

 The summit-level commences with Okefinokee 

 Swamp, 11J. miles above Camp Pinckney, and 

 is 62 miles in length. It runs 22 miles through 

 the swamp, and 14 miles beyond the point where 

 it emerges it meets the Suwanee River, which 

 is to serve as the feeder of the canal. The wa- 

 ters are to be raised to the level of the canal, 

 and diverted into it by means of a dam, w r hich 

 will produce an artificial lake near Blount's 

 Ferry. From this Jake to the end of the sum- 

 mit-level the distance is 18 miles. It descends 

 on the Gulf side by two locks of 10 feet lift, 

 then five of 15, and one of 10-feet lift. The 

 line crosses the Allapaha and Withlacoochee 

 Rivers, and is carried through the center of 

 San Pedro Bay. A channel must be dug, and 

 protected with jetties, for 7i miles to deep 

 water. The drainage area tributary to the 

 summit-level is 1,200 square miles, in which 

 the average annual rainfall is about four feet 

 six inches. The cost of the canal, according 

 to the plans proposed, would be about $50,- 

 000,000. These plans contemplate a canal 25 

 feet in minimum depth, 80 feet wide at the 

 bottom, and 108 feet wide at the water-level. 

 The locks are to be 25 feet deep on the sills, 

 and to have a width at the gates of 65 feet, 

 and a length of 500 feet in the chambers. 

 They have the same dimensions as those of 

 the projected Panama Canal, and differ from 

 them only in the lifts. They are to be dual 

 locks, a reserve lock being placed by the side 

 of each working lock so -that traffic may not 

 be arrested while it is being repaired. To en- 

 able ships to pass each other the canal is to be 

 widened to 155 feet at bottom and 255 feet at 

 the water-surface, for 1,000 feet above and be- 

 low each pair of locks; and other basins for 

 the same purpose are to be placed at intervals 

 of six miles along the line. To earn current 

 expenses and 5 per cent, interest on the cost of 

 construction, estimated at $50,000,000, 10,714,- 

 300 tons must pass through annually if the 

 canal-toll is fixed at 28 cents per ton, and a traf- 

 fic of 1,750,000 tons would have to pass through 

 in order to enable the current expenses and 

 cost of maintenance to be met. The actual 

 tonnage which passed through Florida Straits 

 in 1879 was about 2,600,000; but this traffic 

 will probably be much larger in future as a re- 

 sult of the improvements at the mouth of the 

 Mississippi. It has been computed that the 





