PRACTICAL BOOK OF GARDEN ARCHITECTURE 



from a decorative standpoint, but also insures 

 greater safety in times of freshets. 



Lakes of good dimensions, dammed to receive an 

 abundant natural water supply, may give consider- 

 able cause for anxiety concerning a possible ' 'bursted 

 dam." There seems to be a general impression that 

 a dam usually bursts in the sense that the pressure 

 of water forces it out, and that therefore the garden 

 lake should not be large enough, even on the grounds 

 of an extensive country seat, to hold water sufficient 

 to burst the dam. There need be no cause for alarm 

 in this respect, for there will be little danger of the 

 dam being forced out because of the pressure of 

 water back of it. If it should give way, it probably 

 will be because a leak has occurred, which has be- 

 come larger as the water has seeped through, until 

 finally the leak lets out the water in a rush. Another 

 cause for a so-called "bursted dam" is an overflow 

 wash-out, when the spillway has not been constructed 

 large enough to carry off a great quantity of surplus 

 water. The spillway built for only the usual strong 

 flow that forms the water-fall, will be decidedly 

 inadequate when streams and lakes are swollen 

 from long-continued rain storms. When the spill- 

 way cannot carry off the greater flow that has been 

 created, the surplus starts over the dam at some other 



point, where preparation has not been made for it. 



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