The result of the whole is as follows: The length from the Pacific to the The sum of the ascents is... The sum of the descents is.. The difference is the height of the lake above the Pacific Feet.in. dec 1047 5.45 128 3.05 We now come to the communication with the At- ROUTE OF THE CANAL. 411 to Mr. Bailey's soundings, fifteen fathoms of water. The length of the river, by measurement, with all its windings, from the mouth of the lake to the sea, is seventy-nine miles. There are no cataracts or falls; all the obstructions are from rapids, and it is at all times navigable, both up and down, for piraguas drawing from three to four feet of water. The From the lake to the river of Los Savalos, about eighteen miles, the depth is from two to four fathoms. Here commence the rapids of Toros, which extend one mile, with water from one and a half to two fathoms. The river is then clear for four miles, with an average depth of from two to four fathoms. Then come the rapids of the Old Castle, but little more than half a mile in extent, with water from two to four fathoms. river is clear again for about two miles, with water from two and a half to five fathoms, where begin the rapids of Mico and Las Balas, connected and running into each other, and both together not more than a mile, with water from one to three fathoms. Then the river is clear one mile and a half to the rapids of Machuca, which extend a mile, and are the worst of all, the water being more broken, from running over a broken rocky bottom. The river then runs clear, and without any obstruction for ten miles, with water from two to seven fathoms, to the River San Carlos, and then eleven miles, with some islands interspersed, with water from one to six fathoms, to the River Serapequea, the measurements of one fathom being about the points or bends, where there is an accumulation of sand and mud. It then continues seven miles clear, with water from two to five fathoms, to the Rio Colorado. The River Colorado runs out of the San Juan in another direction into the Atlantic. The loss to the latter, according to measure ment taken in the month of May, 1839, was twentyeight thousand one hundred and seventy-eight cubic yards of water per minute, and in the month of July of the same year, during the rising of the waters, it was eighty-five thousand eight hundred and forty yards per minute, which immense body might be saved to the San Juan by damming up the mouth of the River Colorado. From this point there are thirteen miles, with soundings of from three to eight fathoms. The bottom is of sand and mud, and there are many small islands and aggregations of sand without trees, very easily cleared away. The last thirteen miles might be reduced to ten by restoring the river to its old channel, which has been filled up by collections, at points, of drifted matter. An old master of a piragua told Mr. B. that within his memory trees grew half a mile back. The soundings were all taken with the plottingscale when the river was low, and the port of San Juan, though small, Mr. Bailey considers unexceptionable. The foregoing memoranda were placed in the hands of my friend Mr. Horatio Allen (now engaged as engineer on our Croton Aqueduct), who has kindly prepared from them the plan opposite. I ought perhaps to remark, for the benefit of those who are not familiar with such plans, that in order to bring the profile of the country within a small compass, the vertical lines, which represent elevations and depressions, are on a scale many times greater than the base lines or horizontal distances. Of the former, the scale is one thousand feet, and of the latter it is twenty miles to the inch. This, of course, gives a distorted view of the country; but, to preserve the relative proportions, it would be necessary for the base line in the plan to be one thousand times longer. The whole length of the canal from the Lake of Nic |