IMPROVEMENT OF RIVER FLATS. 257 



tity of suspended matter is carried down, is arrested or 

 retarded, and made to deposit its burden. 



When land is to be thus reclaimed, the first thing to be 

 looked to is the nature of the outfall for future drainage, 

 when the newly made ground requires to be dried and 

 made fit for cultivation ; the second is, to be sure that the 

 amount of solid matter carried in suspension by the 

 stream, is sufficient to warrant the expectation that the 

 process will be completed in a reasonable period of time, and 

 at a cost that will not surpass the probable future value of 

 the land. When these points are decided favorably, the 

 next thing is, to choose the method by which the work may 

 be done ; as one method may be used, by which eight or 

 twelve years may be required to do the work which may 

 possibly be done in two or three years, by another method. 

 Thus, by simply retarding the flow by cross-lines of 

 stakes, with brush wattled between them, or by coarse 

 basket work or gabions anchored with stone and deposited 

 in lines, which is the least expensive plan, some years may 

 elapse before the ground may reach the hight of ordinary 

 high water, and become solid enough to sustain an em- 

 bankment ; when by throwing up banks of mud upon 

 foundations of piles and gabions filled with earth or 

 gravel, and making sluices so as to enclose the muddy 

 water and retain it until its load^ has been dropped, when 

 the clear water could flow off, a depth of soil of from 

 one foot up to four or five feet has been gained in one 

 year. Generally the process is a very slow one, and be- 

 fore the work is undertaken some trustworthy estimates 

 should be procured, as to the cost of the work, and the 

 probable length of time that may be required for its com- 

 pletion. 



The erratic course of rivers and their fickle behavior 

 when in flood, is an element that deserves close study. 

 Much of this depends upon the geological character of 

 the banks, as well as upon the velocity of the stream. 



