Page:Popular Science Monthly Volume 60.djvu/560

552 of 24.8 miles, the cost $16,000,000 and to require nine years to build.

This route was selected because it would be possible to construct the locks in the solid ground of the island and, though not the shortest line that could be selected, it would be in the shallowest water and so far south that some of the streams flowing into the sea would have their outlets outside of the district to be drained. Along the top of this dyke it is intended to have a railroad, thereby shortening the distance by rail from North Holland to Groningen by 35 miles—a matter of considerable importance in a country where no distances are great.

By shutting out the North Sea, the water left in the Zuider Sea would be fresh, and it was feared that this change would cause the death of the vegetation along the shores and that sickness would result from its decay. But the freshening process would be so gradual that there would be abundant opportunity for an adaptation of vegetation to the changing conditions. The entire scheme contemplates a step-by-step process. That is, after completing the sea dyke, so that the inflow of water can be stopped and the outflow regulated by the use of the sluice gates, it is proposed to surround in the northwest corner of the imprisoned sea about 52,620 acres and from this pump out the water. As fast as the land within this dyke should become free from water it would be subdivided by ditches like the rest of Holland and placed under cultivation at the earliest possible moment. It is believed that this can be done in five years and that the cost would be about $5,000,000.

The portion of the sea to be included in this, as well as in other polders, the name given to drained areas, has been determined from many thousand borings, and also from the desire to avoid stopping up or diverting any of the larger streams that now empty into the sea.

After putting this polder in good shape, the southeast corner will be dyked in and the water pumped out, yielding ultimately 249,000 acres. This will require ten years and the cost is estimated at $24,740,000. After this shall have been completed 77,800 acres will be enclosed in the southwestern section of the sea. The work of converting this into arable land will require four years, and cost $9,140,000. The last section to be drained will be in the northeast, where $125,649 acres will be added to the domain after five years' work at an estimated cost of $14,000,000.

The polders have been selected so as to leave undisturbed every important city now on the sea, and also to allow all the rivers to empty into the part of the sea not included. The plan also contemplates the deepening of the mouth of the Ysel, the broadening of the entrance to Amsterdam, and the improving of the outlets of all the rivers now emptying into the Zuider Sea, in this way bettering the condition of