Back of each pair of gates is a second pair of emergency gates folded back flush with the wall and only to be used in case of injury to the first pair. On the floor of the canal at the entrance to the lock lies a great chain, attached to machinery which, at the first sign of a ship’s becoming unmanageable, will raise it and bar the passage. Nearly all serious accidents which have occurred to locks have been due to vessels of which control has been lost, by some error in telegraphing from the bridge to the engine room. For this reason at Panama vessels once in the locks will be controlled wholly by the four locomotives on the lock walls which can check its momentum at the slightest sign of danger. Their own engines will be shut down. Finally at the upper entrance to the locks is an emergency dam built on the guide wall. It is evident that if an accident should happen to the gates of the upper lock the water on the upper level would rush with destructive force against the lower ones, perhaps sweeping away one after the other and wrecking the canal disastrously. To avert this the emergency dams are swung on a pivot, something like a drawbridge, athwart the lock and great plates let down one after the other, stayed by the perpendicular steel framework until the rush of the waters is checked. A caisson is then sunk against these plates, making the dam complete.
The method of construction and operation of these locks will be more fully described in a later chapter. What has been outlined here can be fully observed, by the voyager in transit. The machinery by which all is operated is concealed in the masonry crypts below, but the traveler may find cheer and certainty of safety in the assurance of the engineer who took me through the cavernous passages—“It’s all made fool proof”.
Photo by Underwood & Underwood
LOCK AT PEDRO MIGUEL UNDER CONSTRUCTION
The picture shows strikingly the construction of the locks in pairs, the inner pair being for precautionary purposes
RANGE TOWER AT PACIFIC ENTRANCE
RANGE TOWER AT PACIFIC ENTRANCE