WORKS FOR CREATING SLACKWATER. 135 



To bore into the rock in sedimentary streams, a large pipe may be driven and 

 the sand removed therefrom with a sand-pump. When the pipe has been driven to 

 bed-rock and pumped out, the ordinary drill or diamond drill may be used to ascer- 

 tain the thickness and character of the stratum. Borings should be made into it at 

 several places for a depth of eight or ten feet, since it frequently happens that a top 

 crust covers a layer of softer material, and unless the presence of the latter be discov- 

 ered in time, it may lead to annoying if not dangerous results. A sufficient number 

 of holes should be put down to fully determine the profile and character of the founda- 

 tion. When no bed-rock exists within a reasonable distance or where the material 

 found is unsuitable for a foundation, it will probably be necessary to build on piles, in 

 which case the borings need not be so numerous nor so complete. 



After the borings and soundings have been completed, and maps and profiles 

 made, the exact position of the lock and dam may be determined and the plans pre- 

 pared. 



Acquisition of Land. When the site has been decided upon, the necessary land 

 must be acquired by purchase or by condemnation. This is usually one of the most 

 tedious portions of the work, since titles have to be examined, heirs located, etc., and 

 in many cases the only way to secure a clear title is to have the land condemned. We 

 have met with cases where two or three years have elapsed before proper title deeds 

 could be obtained. 



On the lock side, the amount purchased should be sufficient to allow plenty of 

 yard room during construction, as well as good sites for the dwelling-houses. It should 

 extend above the lock about six hundred feet (or more if the bank has to be cut away 

 to widen the approach), and below the lock, unless the banks are very stable and the 

 river not subject to high floods, in a narrow strip of not less than eight hundred to 

 twelve hundred feet in length, since the wash from the dam will attack the bank along 

 that distance. 



On the abutment side, it will usually be enough to purchase a width sufficient to 

 extend fifty or a hundred feet back from "the top of the bank after the latter has been 

 finished to grade. Above the abutment the property may continue about three 

 hundred feet, and below it, the same distance as on the opposite bank. 



In addition to the above, a right of way should be purchased from the lock to the 

 nearest county road, so that communication will always be open. 



In the majority of instances, far too little land is secured, as the impression is 

 apparently in vogue that it is unnecessary, or can be purchased later. The result is, 

 either that the neighboring property becomes badly damaged along the river-front, 

 causing perpetual friction with the owners, or that the land has to be purchased 

 after all, involving additional legal expenses and complications in examining the titles, 

 and a higher price charged for land. It would appear to be much the wiser plan to 

 buy a sufficient amount at first, -since the extra cost will be a very small percentage of 

 the whole cost of the construction. 



