l82 



SCIENCE. 



[Vol. X. No. 245 



the 50 acres, there is a net profit of $4,125 from the acreage planted. 

 This is clear net profit on the cane, and does not include any 

 charge of profit to the people owning the mill or plant. Kansas has 

 offered a premium of 2 cents a pound for all the sugar produced in 

 that State, and there are 1 50,000 acres of sorghum grown there, and 

 nearly a million dollars' worth of machinery has been built for ex- 

 periments in testing the best manner of extracting the juices. 

 Sorghum-sugar can be raised anywhere from the Gulf to Minnesota 

 at less than i cent per pound ; in fact, one of the sugar engineers of 

 Cuba, after examining the results at Fort Scott, stated that he could 

 put up a plant which would produce sorghum-sugar at 59 cents per 

 hundred pounds. There is no reason why a bounty of $500,000 a 

 year should not be given to sugar, and as much more to flax, by the 

 government. In thus co-operating with State experimental stations, 

 an unexampled prosperity should result from these endeavors." 



THE NICARAGUA CANAL. 



On April 24, 1887, the contract between the Nicaragua Canal 

 Association and the Republic of Nicaragua was signed, and the 

 work on this important route from the Atlantic to the Pacific will 

 therefore soon be taken up. ' 



The principal surveys of the route are those made by O. W. 

 Childs, in 1850-54, on behalf of the American Atlantic and Pacific 

 Ship Canal Company, and those of the United States Surveying 

 Expeditions, 1872-73 and 1885, the former under Commander 

 Hatfield and later under Commander Lull, the latter under A. G_ 

 Menocal, who was chief civil engineer of the expedition of 1872-73. 

 Our map is compiled from the maps and profiles published in the 

 reports of these expeditions, and shows the locations of the canal 

 in 1872 and 1885. 



Lake Nicaragua, which occupies the central part of the isthmus, 

 will form the summit-level of the canal. Its outlet is the river 

 San Juan, which flows to the Caribbean Sea. Near the lake the 

 river is broad and flows through an open country. It has an aver- 

 age depth of nineteen feet. Twenty-eight miles below Fort San 

 Carlos the river enters a hilly country and forms numerous rapids 

 which obstruct navigation. The last of these are the Machuca 

 Rapids, below which the river has a depth varying from 20 to 60 

 feet, with but little current : this section is called ' Agua Muerte,' 

 or dead water. At the foot of the Agua Muerte the San Carlos is 

 received into the river, and is the first considerable tributary. 

 This river comes from a long distance up in the Costa Rica hills, 

 and carries a considerable amount of detritus which consists 

 chiefly of volcanic sands. Below the confluence the San Juan 

 changes its character altogether, and is filled with shoals and sand- 

 bars. An additional amount of detritus of a similar character is 

 carried into the San Juan by the Serapiqui. While the upper course 

 of the San Juan, which is almost exclusively fed by Lake Nicaragua, 

 is not subject to freshets, its lower part, below the confluence of 

 the San Carlos, partakes of the character of that river, which is a 

 torrent during the rainy season, and has little water during the dry 

 season. Therefore the lower part of the river cannot be made use 

 of for navigation, and an independent canal to the Caribbean Sea 

 must be built. In the location of 1872-73 the canal followed the 

 river, and then crossed its delta to the lagoon of Greytown. 



Thirteen miles below the confluence of the Serapiqui the delta of 

 the San Juan begins. The principal arm of the river is the Rio 

 Colorado, which flows to the eastward and empties into the sea. 

 The other arm is the Lower San Juan, which passes more to the 

 northward, and is divided into several mouths, which discharge their 

 waters into the sea and into the lagoon of Greytown. The delta 

 consists of the light volcanic sand carried into the San Juan by its 

 southern tributaries. This silt has almost totally destroyed the 

 harbor of Greytown by closing up the old entrance and filling a 

 great part of the harbor. The silt is being carried into it by the 

 Lower San Juan and the current. Therefore it is proposed to cut 

 off the Lower San Juan, to send all the water through the Colorado 

 into the sea, and to build a jetty for keeping the silt out of the 

 harbor, which will be improved by dredging. 



When the project of a canal through Nicaragua was first dis- 

 cussed, several routes from the lake to the Pacific Ocean were pro- 



posed. The one advocated by Napoleon ran from the lake through 

 the Rio Tipitapa to Lake Managua, and continued to the port of 

 Realejo. This route, as well as those to Salinas Bay and San 

 Juan del Sur, was found impracticable, and Brito at the mouth of 

 the Rio Grande was chosen as terminus. The upper Rio Grande 

 offers several difliculties on account of the freshets of the river and 

 the narrowness of its valley. This induced Commander Lull to 

 select the Rio del Medio route, though it requires deeper cuttings,, 

 as it avoids the upper part of the Rio Grande, while Menocal favors 

 the Rio Lajas route. 



The route proposed by Mr. Menocal extends from the harbor of 

 San Juan del Norte, or Greytown, on the Caribbean Sea, to the 

 port of Brito, on the Pacific, a total distance of 169.8 miles, of 

 which 40.3 miles are canal in excavation, and 129.5 miles open 

 navigation through Lake Nicaragua, the river San Juan, and the 

 basin of the river San Francisco, a tributary of the San Juan. Lake 

 Nicaragua, some 90 miles long by about 40 miles wide, the sur- 

 face of which is 1 10 feet above sea-level, has been taken as the 

 summit-level of the canal. Leaving the harbor of Brito, the canal 

 follows the valley of the Rio Grande with a gradual inclination of 

 about 12 feet to the mile, ascending by means of four locks, 26 to- 

 29 feet lift, to the summit-level extending 8.5 miles west of the 

 lake. From that point the canal extends easterly, and, cutting 

 across the divide with a maximum depth of 41.4 feet above the 

 surface of the water, reaches the lake 17.27 miles from the Pacific 

 terminus. The summit of the divide cut through by the canal, 

 1 5 1 .4 feet above sea-level, is much the lowest depression across the 

 American isthmus. 



The lake navigation extends from the mouth of the river Lajas 

 to Fort San Carlos at the head of the river San Juan : through that 

 distance not less than 28 feet of water can be carried to within 

 2,400 feet of the west shore, and eight miles of Fort San Carlos. 

 For the former distance, dredging and rock excavation are neces- 

 sary ; and in the latter, dredging in mud to an average depth of 

 3.5 feet, to extend deep water from shore to shore. Other parts of 

 the lake are verj' deep. 



The canal then follows the river San Juan for a distance of 

 64 miles from the lake to Ochoa, just below the confluence of the 

 river San Carlos {v. map). Here a dam is proposed, 1,255 feet long 

 and 52 feet high, which will back the water of the river the entire 

 distance to the lake, maintaining the surface of the latter at the 

 proposed level of 1 10 feet. The upper part of the river thus 

 deepened and widened will be converted into an extension of the 

 lake, at no place less than 1,000 feet wide, arid, with the exception 

 of the first 28 miles from the lake, the depth gradually increases 

 from 28 to 130 feet. Within those 28 miles, dredging and rock 

 excavation to an average depth of 4 feet will be needed for a dis- 

 tance of 24 miles. The dam is located between rock abutments, 

 and is proposed to be built of concrete resting on rock foundations 

 20 feet below the present water-level. 



Just above the dam, a break between the hifls confining the 

 river on the north, affords a desirable basin at the entrance of the 

 canal, which here leaves the river. After running a distance of .62 

 miles through the basin, it cuts across a broken country for a dis- 

 tance of 1. 82 miles, and enters the valley of the creek San Francisco. 

 This creek runs nearly parallel to the San Juan, from which it is 

 separated by a range of hills, to a point about 9 miles from the 

 dam, then, receiving a tributary from the north-east, turns 

 abruptly to the south and empties into the San Juan. Its 

 valley forms an irregular, flattened Y, with its foot resting 

 on the San Juan, one arm extending westerly to within a 

 short distance of the dam at Ochoa, the other easterly in 

 the direction of Greytown. Across the stem of this Y will be built 

 an embankment 6.500 feet long on the crest, with a maximum 

 depth of 51 feet. This embankment will retain the waters of the 

 San Francisco, forming an artificial lake of 30 to 50 feet depth, at 

 the level of the river above the dam, or an extension of the summit- 

 level. The outlines of this lake and the increase in width of the 

 San Juan, after its waters are dammed up at Ochoa, are shown in 

 our map according to information kindly furnished by Mr. Menocal. 

 The extent of country which will be inundated by the San Carlos 

 cannot be defined, as the valley has not been surveyed. As its 

 character, however, is similar to that of the San Juan, the strip of 



