202 



Doc. No 75. 



tively erroneous in some particulars ; as^ for instance^ the distance from 

 Lake Managua to Realejo, so far from being only 29 miles, is actually 40 

 to 45 miles. That the calculation is generally erroneous will appear from 

 the following facts : The port of San Juan is in 10° 56' N. latitude, and 

 83° 42' W. longitude ; the port of Realejo is in 12° 27' N. latitude, 87° 

 9' W. longitude; consequently the distance in a right line between the 

 two points is 265 standard miles, or only 13 miles less than the distance 

 computed by Napoleon's authorities — a margin altogether too small for 

 the augmentation of length consequent upon the variations of the route 

 from a right line. The actual distances can only be determined by actual 

 measurement; but I nevertheless venture to submit the following calcu- 

 lations : 



Length of the river San Juan - - - - 90 miles. 



Length of the port of Lake Nicaragua necessary to be trav- 

 ersed 110 miles. 

 Length of river Tipitapa - - - - - 18 miles. 

 Length of [iake Managua - - - - - 55 miles. 

 Distance from lake to Realejo - - - - 40 miles. 



Total - - - - - 303 miles. 



From this must be deducted 25 miles, in case the line is terminated at 

 the port of Tamarinda ; in case it should terminate in the Gulf of Fonseca, 

 it is not probable it would be many miles longer than the Realejo line. 

 The extent of actual canalization would therefore be, to Realejo 148 miles; 

 to Tamarinda 123 miles; and to the Gulf of Fonseca, probably, 135 

 miles. 



The height of the various lakes to be passed, and the elevations of land 

 to be overcome, 1 have employed no means of ascertaining with accuracy. 

 From my observations, however, I am disposed to regard the following 

 statement as very nearly correct : 



Above the Atlmtic. Above the Pacific. 



Height of the lake of Nicaragua - 147 ft. 9 in. 128 ft. 3 in. 



Height of the lake of Managua - - 176 ft. 5 in. 156 ft. 11 in. 



Highest point of land to be passed - 231 ft. 11 in. 212 ft. 5 in. 



The accompanying section. No. 3, is on the horizontal scale of 15 miles, 

 and the vertical elevation of 500 feet to the inch ; that is to say, a vertical 

 scale proportionably 160 times greater than the horizontal. 



It is useless to enter mto calculations respecting the proper size and 

 respecting the cost of such a work as the proposed canal. Its dimensions, 

 in order to make it fully answer the purpose of its construction, must be 

 suflticiently great to admit the easy passage of the largest vessels. Its cost, 

 until there is a detailed survey of the entire line, must be entirely a mat- 

 ter of conjecture. It has been variously estimated from six to twenty-five 

 and thirty millions of dollars. Assume it to cost ,^100,000,000, which 

 may be as near the truth as any other calculation; still it is enough to 

 know that it is feasible, and that its benefits, immediate and prospective, 

 will be sufficient to compensate for the expenditure of double that amount^ 

 startling as it may at first appear. 



