The first step in the construction of the dam was to dam the Chagres then flowing through its old channel near the site chosen for the spillway, and through the old French canal. This was accomplished by building parallel walls, or “toes” of broken stone and filling the space between with fluid mud pumped from the old channel of the stream. A new channel of course was provided called the “west diversion”. The toes are about a quarter of a mile apart and rise about 30 feet high. They were built by the customary devices of building trestles on which dump trains bearing the material were run. After the core of fluid silt pumped in between the walls had begun to harden, dry earth was piled upon it, compressing it and squeezing out the remaining moisture. As this surface became durable the railroad tracks were shifted to it, and when I visited the dam in 1913 the made land of the dam was undistinguishable from the natural ground surrounding it. Over it scores of locomotives were speeding, dragging ponderous trains heavy laden with “spoil” from the Culebra Cut. From the crest on the one hand the dam sloped away in a gentle declivity nearly half a mile long to the original jungle on the one side, and a lesser distance on the other, to the waters of the Gatun Lake then less than half filled. When the main body of the dam had been completed and the spillway was ready to carry off the waters of the Chagres then flowing through the “west diversion” the task of damming the latter was begun. This was the first effort to stem the current of the Chagres, the river dreaded for so many reasons, and the description by Lieutenant Colonel William L. Sibert, the engineer in charge of this division, will be of interest: [Illustration: COPYRIGHT, 1913, BY F. E. WRIGHT A NATIVE BAKERY The Panamanian never does anything indoors that he can do in the open. The village bakery, the village mortar or mill and the village laundry are social meeting places used by all.] [Illustration: GATUN UPPER LOCK] [Illustration] [Illustration: _Photo by Underwood and Underwood_ CENTER: GATUN CENTER LIGHT; LOWER CORNER: EMERGENCY GATES]