At this lock, excavated in the rock foundations of a spur of the northern hills, the summit level, reaching back through the San Francisco basin, up the San Juan, and across the lake to the first lock on the west side, a distance of 144·8 miles, ends, and the canal, lowered 53 feet by the lock, passes by easy curves down the widening valley of the Deseado to the next lock, less than a mile beyond. Here another drop of 27 feet occurs, and then the canal follows the still widening and gradually descending valley in a north-easterly direction for less than three miles to the third and last lock at the mouth of the valley. This lock lowers the canal to the sea level, and from here it takes a direct course across the flat low basin of the San Juanillo and the Lagoon region, to the harbour of San Juan del Norte, or Greytown, about 11½ miles distant. The surface drainage to be provided for in this division is not extensive, and it is especially small on the western slope of the “divide,” where three short artificial channels will divert it all into the San Francisco Lake at some distance from the canal. Across the “divide,” and as far as the first intersection of the canal and the Deseado, the natural drainage is away from the canal. From this point to the San Juanillo the canal will be protected on both sides by drains formed partly by the present bed of the Deseado, and partly by artificial channels. The remainder of the canal, through the lowland from the San Juanillo to Greytown, will be protected by embankments formed by the material deposited by the dredgers, an artificial channel being cut on the south to divert the San Juanillo, and another on the north to give Laguna Bernard and its tributaries an independent outlet to the sea. From the last lock to Greytown the canal is enlarged, as at Brito, on the west side, forming an extension of the harbour 11½ miles inland. The material to be excavated in this division is sand, gravel, and alluvial soil (all dredgable material) for a distance of 12 to 15 miles from Greytown, then clay, gravel, and rock in the deeper cuts, and finally, in the “divide,” cut rock, which will be utilised as on the west side, in the construction of the embankment, in the breakwater at Greytown, in pitching the canal slopes, and in concrete for the dam and locks. About 27 miles of the actual canal will be ordinary excavation, and it is proposed that the remaining 13 miles will be largely, if not entirely, excavated by dredgers. In the western division, the excavation of the portion of the canal between the last lock and the Pacific by dredgers will solve the problem of the drainage of the work for that division, as on the remaining excavation, being above sea-level, the question of drainage will be perfectly simple. In the eastern division, as in the western, the portion of the canal between Greytown harbour and the first lock, a distance of 11½ miles, will be dredged.