THIS is the same lock nearer the gates, and shows the great length of it from gate to gate and something of its building and construction, from my point of view.
XX
THE WALLS OF PEDRO MIGUEL
THIS was drawn from the opposite end of the lock and the great side walls topped with their concrete-making crenellations and cranes are seen. In the foreground, on the left, is one of the side openings for emptying the water from one lock to another—for all the locks are double, side by side, and ships will not have to wait until a lock is empty, as is usual, before they can enter, but, as one empties, the same water partly fills the one beside it, and so steamers will pass without waiting. Two or three small vessels can go through at the same time, as well as the largest with room to spare.
