whereas the Gatun Dam was built with a slope of about one in ten. The foundation was simply spread, making the dam about a third of a mile through at the base, so that the underlying material would carry the load. This underlying material was compressed under the load in some places as much as 15 feet. As the load was gradually placed on it, the material in the base became more and more compact, until finally settlement has practically ceased.

Every two or three months borings have been made through the material in the dam itself, and that under it, for the purpose of ascertaining any changes in the character of such materials. This data shows that the material, both in the dam and under it, is continually becoming more compact. It stands today, safely carrying its full load, and tomorrow it will be able to carry more.

THE JAMAICAN IS HARD TO KILL

The dam was built by constructing trestles in both edges of it and from these trestles making rock fills or "toes." When these toes had reached a height of 60 feet on the south face and about 30 feet on the north, dredges commenced to pump an impermeable mixture of sand and clay in between them. This central core constitutes the real barrier to the passage of water through the Gatun Dam.

As the hydraulic fill was built up the rock fills were carried up, so as always to constitute levees, holding the additional hydraulic fill. A pipe-line dredge pumps about 20 per cent solid material and 80 per cent water, so in building a dam in this way it is necessary to provide some means for draining off the surplus water.

This was done where the dam joins the hill, a 20-inch pipe being laid in a trench on the rock and carried in to the lower edge of the hydraulic fill. An elbow was then placed on the end of the pipe, and as the water and hydraulic fill rose other sections were added to the elbow. A cage was placed around the intake end of this pipe to keep the drift away, and men were sent occasionally to remove such drift from the pipe intake.

At one time when water was running

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through this pipe under a 30-foot head, three Jamaicans were removing drift and one of them fell in the 20-inch pipe. The other two tried to pull him out but could not. They let him go and ran as quickly as they could to the other end of the pipe. The man traveling in the pipe reached the end first, notwithstanding the fact that he turned a corner at an angle of 90 degrees. His ears were scratched a little!

There was a great deal of emulation between the employees in the different divisions. The part of the story so far told is true, but Colonel Gorgas made the addition that the man jumped up and said that there wasn't anybody on the Pacific Division who could do that.

The spillway over which the surplus waters of the Gatun Lake find their way to the Atlantic Ocean is found on page 170. This is a picture of the spillway when practically complete.

The gates on top are 45 feet wide and the lake will stand 16 feet deep against them when no water is being wasted; consequently if one or more of the gates is lifted water will flow between the piers 16 feet deep. These gates are raised and lowered like a window-sash. These movable gates constitute the regulating works, by means of which the level of Gatun Lake is controlled.

"THE QUEEN OF AMERICA' AND THE
LUNCHEON PARTY

In the beginning but very little provision was made for quarters for families of the canal employees. It soon became evident that order could not be maintained, contentment prevail, and a permanent force kept unless the wives of the men were there; so the commission undertook to build family quarters.

It was announced in circulars, etc., that employees would be provided with family quarters within ten months after arrival on the Isthmus. Not only all the married men immediately applied for quarters, but nearly every unmarried man on the job applied. Family quarters carried with it free light and fuel.

Nearly every one of the young unmarried men the first time they came back from leave brought a wife if they could get one. The building department was