about ten vessels of various sorts in one lock chamber, and even then it was not full. Attention is especially called to one piece of plant in the fleet, and that is the old French dredge, a ladder dredge distinguished by the endless chain with buckets. This old French dredge has served loyally two administrations and is still in the advance guard going to attack Cucaracha slide. By a peculiar coincidence, M. Bunau Varilla, the former chief engineer of the French Canal Company, passed through the locks during this event aboard one of the boats in the fleet. He, as you know, was a great advocate of a sea-level canal.

More precautions have been taken probably in the Panama Canal locks than in any other locks in the world. In addition to having duplicate gates at each end of the lock, a great chain is attached to a system of hydraulic cylinders and kept in the position shown until a boat makes a landing alongside the guide wall and a towing locomotive takes charge of it. Then the chain is lowered into a groove in the bottom of the canal. This fender chain across the entrance is shown in the picture on page 168.

THE FLOATING ISLANDS OF GATUN LAKE

A large part of the bed of what is now Gatun Lake was formerly swamp land. In that swamp were logs on which grass and small trees had grown. When the lake rose, the entire bottom floated. The wind broke it into pieces, sometimes an acre or more in extent, and since that time these pieces have been floating aimlessly about the lake (see page 172).

During the fall of 1912 the water was allowed to flow 6 or 7 feet deep over the uncompleted spillway, and a large number of these floating islands were passed over it. As soon as the lake reaches normal height and water can be spared, these floating islands will be towed systematically to the spillway and passed over and out to the Atlantic.

As the waters of the Chagres River came down and encountered the dam at Gatun the lake was gradually formed, and during this process much vegetation was submerged. As the lake rose it gave the ladies of Panama great opportunities. for collecting orchids.

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The most beautiful orchids have a way of growing on the largest trees, and so high that they are difficult to get; but while the lake was rising to 85 feet above sea-level, one could row around in small boats through the trees and pick them off (see pages 174 and 175). A Kipling should have been at Panama to write a jungle story that would describe the action of the wild animals when this great permanent flood of the Chagres came.

The last natural barrier that held back the water of Gatun Lake from the cut that had been made across the Continental Divide was the dike at Gamboa. Up to this point the canal has followed the Chagres Valley. It now leaves the valley and cuts across the Continental Divide to Pedro Miguel, and there commences to go down the Pacific slope.

The Gamboa dike was broken down on October 10, 1913, by the explosion of a charge of dynamite which had been stored in it. This charge was fired by the depression of a telegraph key in the White House at Washington by President Wilson (see page 176). Before the dike was blown up, water was allowed to enter the Culebra Cut through pipes, so as to fill it to within 5 or 6 feet of the level of the lake. Had it been blown up with 30 feet difference in level, some damage might have resulted.

THE CULEBRA CUT AND THE SLIDES

The Culebra Cut will, it is thought, be the most striking of all the features of the canal. The Gatun Lake, when all the trees are gone, will be beautiful with its green islands and green promontories ; but the most striking feature, I think, will always be the great cut across the Continental Divide.

The most difficult slides to handle have occurred in that part of the canal near the Continental Divide, marked by Gold Hill and Contractor's Hill, all comprised in a length of about 11⁄2 miles of canal. Just beyond Gold Hill is the famous Cucaracha slide (see pages 147 and 151). the surface of which was above the lake level when the water entered Culebra Cut, and it prevented the water from flowing through the cut to Pedro Miguel.

An unsuccessful attempt was made on the same day that the dike at Gamboa

The gate on which all the men are standing, while watching the lower chamber of the lock being filled for the first time, is the sea gate or guard

gate (see page 159)

was destroyed to blast a channel through this slide. A ditch, however, was finally made across it, through which that part of the canal between Cucaracha and Pedro Miguel was filled with water. This allowed dredges to be towed from the Pacific end of the canal to assist those already brought from the Atlantic side in completing the channel excavations.

The Cucaracha slide has broken back to the crest of the hill behind Gold Hill, a half a mile or more from the prism. Since the slide is now broken back to the crest of the hill, and since the face of the hill away from the canal is being artificially removed, a fairly close calculation can now be made as to the number of cubic yards of material that can slide into the canal from that source and the approximate time that it will take to remove it.

A large part of the material composing this slide is clay, and it is hoped that it can be removed by pipe-line dredges. By placing a relay pump in the pipe-line, material can be forced over the banks of the canal. The pipe-line dredge is very efficient in digging and transporting material away from the site, providing the distance or lift is not too great. Material can be so transported from a half to three-quarters of a mile with great ease.

One of the dredges getting ready to attack the Cucaracha slide from the south is shown in the picture on page 148. This dredge came from the Pacific side, and across the slide can be seen the smokestack of the dredge that came from the Atlantic through the Gatun locks. It is hoped that within two or three months a channel can be made of sufficient width and depth for the passage of ships. How