510 



INTEROCEANIC CANAL. 



double system of locks at each change of level. 

 The summit-level of the canal would by Blan- 

 chet's plan take up 237 of the 292 kilometres 

 of the total length of the canal, and would 

 consist of two artificial lakes and Lake Nica- 

 ragua, with which they would be connected 

 by two narrow channels, one at the head of 

 the San Juan and one through the Guyscoyol 

 Pass. These lakes, filling the valleys of the 

 rivers, would be broad sheets on which ships 

 could ride abreast or pass each other under 

 full headway. The depth of 9 metres would 

 be maintained through the whole length of the 

 canal. The material to be excavated is esti- 

 mated at 30,000,000 cubic metres, of which it 

 was hoped that the action of the water would 

 remove about half. The estimated cost of this 

 project is 362,000,000 francs. 

 A project submitted by M. Mainfroy pro- 



Eosed to excavate the canal in the clay of the 

 )ft bank of the San Juan, leaving the bed of 

 the river 12 kilometres below the lake, and de- 

 scend to the sea by 6 double locks ; and on the 

 Pacific side to carry the canal through the 

 valley of the Sapoa Kiver, and make the ter-\ 

 minus the Bay of Salinas. 



M. Belly presented a theoretical scheme ac- 

 cording to which the San Juan River could be 

 restored to the navigable state in which it is 

 reported to have been in the seventeenth cen- 

 tury from the Caribbean Sea to the Lake of 

 Nicaragua, by clearing away the rocks in the 

 rapids and turning the waters of the Colorado 

 branch into the San Juan outlet. 



The American isthmus contracts in the re- 

 gion of Panama to its narrowest dimensions. 

 The rocky barrier between the two oceans at 

 the Isthmus of Panama is only 55 kilometres 

 as the crow flies, and at the Isthmus of San 

 Bias only 50 kilometres. The pass at Cule- 

 bra, through which the Panama Kailroad finds 

 its way, is only 87 metres above the mean tide- 

 level, the lowest pass of the whole isthmus 

 after that of Guyscoyol. The survey of this 

 region by Lull, with Menocal as engineer-in- 

 chief, in 1875, commanded by the United 

 States Government, led them to the conclu- 

 sion that a tide- water canal was commercial- 

 ly impracticable ; and they therefore confined 

 their studies to a project of a lock-canal. 

 The bays of Colon and Panama being settled 

 upon as the most convenient termini, the route 

 must necessarily cross the course of the Cha- 

 gres Eiver ; and in order to avoid the dangers 

 with which the excessive floods in that river 

 would threaten the canal, it was decided to 

 carry the canal across by a high aqueduct at 

 Matachin, whose bottom would have to be 30 

 metres above the sea-level. The depth of 8 

 metres chosen for the canal would make the 

 water-line here 38 metres above tide-water, 

 which elevation would be the summit-level of 

 the canal. The daily outflow through the 80 

 locks, 40 on each side, by which the descent 

 to the two oceans is effected, would amount to 

 about 950,000 cubic metres, which would be 



supplied from the Chagres Eiver by means of 

 a dam between two rocky walls through which 

 the river flows a few kilometres above, and 

 conducted by the aid of a subterranean duct 

 4,000 metres long into a broad basin through 

 which the canal passes. The canal would go 

 through the Culebra Pass, crossing the divide 

 a little to the east of the railroad, descending 

 into the valley of the Rio Grande, and leaving 

 it on the right to enter the harbor 400 metres 

 to the east of the railroad quays. No streams 

 except insignificant brooks would be allowed 

 to discharge into the canal. The Rio Grande 

 would have to be deflected into a new channel, 

 and an outlet canal constructed to receive its 

 affluents from the east. On the Pacific side 

 11 alignments would be necessary, with curves 

 of not less than 1,500 metres radius ; on the 

 Atlantic slope there would have to be 28 

 alignments and curves, with radii as short aa 

 760 metres. The displacement of earth neces- 

 sary for the execution of this project would 

 amount to 37,000,000 cubic metres, and the 

 total cost to about 480,000,000 francs. In pre- 

 senting this plan to the Congress, Menocal de- 

 clared it decidedly less desirable than the Ni- 

 caragua project. 



When, at the instigation of Ferdinand de 

 Lesseps, the French naval officers Wyse and 

 Reclus, accompanied by M. de Celier, engineer 

 of the Bureau of Roads and Bridges in France, 

 and other explorers and engineers, examined 

 the American isthmus, it was with reference 

 solely to cutting a canal through it at the tide- 

 level, through which the largest ocean steam- 

 ships could pass without stoppage. It was 

 supposed at first that the most favorable line 

 for such a canal was across the Isthmus of 

 Darien, connecting the two large rivers, the 

 Atrato, which flows into the Caribbean, and 

 the Tuyra, which discharges into the Pacific, 

 and running between the parallel and separate 

 mountain-chains of the Andes and the Cordil- 

 leras. A thorough examination of this region 

 revealed the impossibility of digging a tide- 

 level canal here. The same engineers under- 

 took a second expedition at the solicitation of 

 De Lesseps, and under the auspices of the So- 

 ciety of Exploration, constituted with General 

 Turr as its president, and this time located a 

 route for a tide-water canal across the Isthmus 

 of Panama, in nearly the same line as that fol- 

 lowed by the Panama Railroad. Satisfied by 

 their survey that the piercing of the American 

 isthmus by a tide-level canal which would ac- 

 commodate the higher marine, the great iron 

 steamships whose keels are 140 metres long 

 and whose tonnage ranges up to 5,000 tons, 

 is technically feasible, De Lesseps invited, in 

 concert with Henri Bionne, of the Geographi- 

 cal Society, delegations from the different 

 chambers of commerce and societies of engi- 

 neers and statistics to meet in a Congress to 

 discuss the question of an American canal. 

 The Wyse and Reclus project was the one 

 adopted by the Congress. The object of the 



