COMMITTEES ON BEHALF OF THE GOVERNMENT 253 



of the San Juan River in 1873, was not at all hopeful that the 

 suggestions of the committee could be carried into effect. He 

 remarks in his report: 



"A committee of the National Academy of Sciences in 1867 proposed, as a 

 partial remedy for the decay of the river and harbor, the dredging out of the 

 channel of the Lower San Juan and the construction of a weir from Leaf's Island 

 to Concepcion Island. The latter of these is in the main river, near its right bank, 

 and above the forks. The former has now become joined to the angle or point of 

 the mainland between the two branches. Concepcion Island is 2,000 feet from the 

 point. The strongest part of the current runs between the two. The island is 

 constantly cutting away at one place and forming at another, being composed 

 entirely of silt banked around drift-logs which have lodged in the shoal water. 



" The weir, if indeed it could be constructed at all with such a combination of 

 unfavorable conditions, viz., the depth and strength of the water, and the yielding 

 character of the bottom, would be quite as likely to fail in as to effect, the object in 

 view, /'. e., the turning of the current into the Lower San Juan, unless the latter 

 was dredged out to a sufficient width and depth to prevent, by drawing it away, 

 the water from cutting around the dam. This would have to be done for a dis- 

 tance of thirteen miles. I confess myself to have been very much discouraged 

 when these facts and convictions impressed themselves on my mind." 65 



On account of these conditions, he proposed to eliminate the 

 Lower San Juan and carry the traffic in a canal which should 

 leave the river at a point about 42 miles from the coast. Recent 

 maps indicate that this plan, with various modifications, was 

 generally accepted down to the time when the interest in an 

 interoceanic canal shifted from Nicaragua to Panama. 



COMMITTEE ON THE PROTECTION OF COAL MINES FROM 

 EXPLOSION BY MEANS OF ELECTRICITY. 1870 



In the Proceedings of the Academy mention of this committee 

 is made under date of April, 1870, in the following terms : 



" Mr. Gould reported in behalf of himself and Mr. Ferrel, the Committee on 

 the letter of Mr. Fua, of Padua, addressed to the President of the United States, 

 in reference to the protection of Coal Mines from explosion by electricity, and 

 referred by him to the Academy, ' That the same communication has been made to 



60 Report of Explorations and Surveys for a Ship Canal through Nicaragua, 1872-73, 

 p. 61. Sen. Exec. Doc. no. 57, 43d Congress, ist Session. 



18 



