CHAPTER II
ON THE CANAL AS IT IS TO BE
BETWEEN Colon and Panama the American Isthmus is about 36 miles across as the crow flies, and is therefore nearly, though not quite, at its narrowest. In this portion of its sinuous course both coasts trend north of east and Panama lies nearly south-east of Colon. The Isthmus in general is a very confused mass of hills and mountains. It is crossed by no transverse trench (such as sometimes occurs in mountainous regions), neither by the trough provided by down-folded strata, nor the rift valley produced by fracture and foundering of rock. A low-level transverse can only be found by following up the course of a river, crossing the divide, and following the course of another river downwards to the other ocean. From the vicinity of Colon, by following up the valley of the River Chagres, we are led in precisely the required direction, i.e., directly towards the Pacific, for nearly two-thirds of the way. The distance from the head of Limon Bay, following the curves of the valley, is 26 miles to this place, Obispo, and for the greater part of the distance the river flows in a broad valley of deep alluvial deposits.
FRENCH DREDGER LAID UP.
FRENCH TRUCKS PARTLY COVERED WITH FOREST GROWTH.
At the point mentioned, the Chagres abruptly changes its course, and, if followed towards its source, will be found to be flowing from north-east to south-west. Moreover, it is now confined to a narrow valley, with steep hills of rocky substance on either side, and its gradient becomes much greater than hitherto. The course of the Canal cannot therefore follow the Chagres valley further. Fortunately, the valley has led us not only a long distance towards the Pacific, but to a place where the dividing ridge only attains an elevation of about 300 feet above sea-level. Striking from Obispo straight for the Bay of Panama, we come in 9 miles to the low alluvial plain of the Rio Grande, which leads straight to the sea in another 6 miles. Thus, from shore to shore, the course of the Canal along this route is 41 miles; but to reach deep water 4-1/2 miles must be dredged beneath the sea at either end, so that the total length of the artificial waterway is 50 miles. Of the land-course less than a quarter, or about 9 miles, is hill country, and most of this is less than 200 feet above the sea. The United States has been committed to this route by the long chain of circumstances already narrated.