74 ANNUAL OF SCIENTIFIC DISCOVERY. 



canal will be decidedly advantageous to several classes of war 

 vessels and to the mercantile marine. Journal Franklin Institute. 



SURVEY OF THE ISTHMUS OF DARIEN FOR AN INTEROCEANIC 



CANAL. 



The expedition for the survey of the Isthmus of Darien to ascer- 

 tain the practicability of a route for the interoceanic canal, under 

 the command of Commander T. O. Selfridge, U.S.N., sailed 

 from New York in the latter part of January, 1870. 



During 6 months of the year, a heavy sea breaks all along the 

 Atlantic border of the Isthmus, and, consequently, the necessity 

 of a good harbor narrows very much the field of research, which 

 a knowledge of the orology of the Isthmus also limits to a corre- 

 sponding degree. There are but 3 harbors on the Atlantic coast of 

 the Isthmus, adapted for the terminus of a canal, the Gulf of 

 San Bias, Caledonia Bay, and the Gulf of Uroba or Darien. The 

 first 2 are magnificent bays, easy of access, and entirely protected 

 from the north winds and heavy swell. The Cordilleras Lloranes 

 skirt the coast at distances varying from 3 to 8 miles, without a 

 break, except at the northern and southern extremities, while the 

 Chiman range, crossing the Isthmus, indicates that in the central 

 portion will be found the greatest amount of mountain area. 



The survey was begun at Caledonia Bay in the latter part of 

 February. The whole face of the country is covered with a prime- 

 val forest, impenetrable from the thick undergrowth but by slow 

 and laborious cutting, through which the surveyor struggles with 

 his compass and level, seeing neither the sky above nor the country 

 around. In these circumstances it was soon evident to the com- 

 mander of the expedition, that the most practical as well as the 

 most expeditious method would be to carry on the survey up the 

 different water-courses. This would give at all times the lowest 

 level, the rivers would lead to passes in the mountains did such 

 exist, and the best results would be obtained in the shortest space 

 of time. As the work proceeded, should any route indicate a level 

 adapted for the proposed line, a more exhaustive survey would be 

 undertaken. 



Reconnoissances with the barometer were made up all the streams 

 emptying into Caledonia Bay, including the Aglamate, Aglaseni- 

 qua, and Washington Rivers. While these were in progress, a 

 reconnoissance in force was made over the mountains to the Pacif- 

 ic slope down the Sucubti, until the villages of the mountain In- 

 dians, the Sucubti tribe, were reached. Here a treaty was made by 

 the commander with them, similar to one with the coast Indians, 

 and the exertions made to show them that we had not come to oc- 

 cupy the country, but merely to look at it, coupled with rigid orders 

 not to molest their property, enabled us at all times to remain on 

 the most friendly terms. 



The result of these explorations failed to exhibit any signs of a 

 pass, and the line up the Aglaseniqua River, thence over the moun- 

 tains, giving the lowest average level, was selected as the one to 

 be surveyed. 



