282 



the project of a canal, from the fear of an im- 

 petuous flowing towards the west, or a diminu- 

 tion of the waters in the Rio San Juan, where, 

 above the ancient Castillo de San Carlos t> are 

 rapids, that are dangerous in time of drought. 

 The art of engineering is sufficiently improved 

 in our days to have no apprehension of such 

 dangers. The lake of Nicaragua may serve as 

 an upper basin, like the lake Oich in the Cale- 

 donian canal, and regulating sluices will fur- 

 nish only as much water for the canal as it re- 

 quires. The small difference of level between 

 the Atlantic and the Pacific Oceans, depends, 

 as I have said elsewhere -f, only on the unequal 

 height of the tides. The same difference is ob- 

 served between the two seas that are joined by 

 the great canal of Scotland ; and if it were six 

 toises, and constant like that of the Mediterra- 



* This small fort, taken by the English in 1665, is vul- 

 garly called El Castillo del Rio San Juan. It is placed, ac- 

 cording to Mr. Juarros, at 10 leagues distance from the 

 eastern extremity of the laguna de Nicaragua. Another 

 small fort was constructed in 1671, on a rock at the mouth 

 of the river. It bears the name of Presidio del Rio de San 

 Juan. Even in the 16th century, the Desaguadero de las 

 %agunas, had fixed the attention of the Spanish government, 

 who ordered Diego Lopez Salcedo to found the town of 

 INiueva Jaen, near the left bank of the Desaguadero, or Rio 

 San Juan ; but it was soon abandoned, like the town of 

 Brussels (Bruselas),. near the gulph of Nicoya. 



f Political Essay on New Spain, Vol, i. p. -32. 



