DAMAGE BY FLOODS IN RIVERS PREVENTION. - 633 
ON THE PREVENTION OF DAMAGE BY 
FLOODS IN RIVERS. 
By C. Napier Bex, M. Inst. C.E. 
Havinc lately been engaged by the New South Wales 
Public Works Department to report on the floods of the 
Hunter River. my attention was turned to a general con- 
sideration of the subject of damage by floods, and how kest 
to guard against them. 
What I have to say on the subject will, no doubt, appear 
to be restricted within a narrow range, as I have no means 
at hand to study what bas been said on the question by 
others, and therefore I can only give my own limited 
experience and ideas on the subject. 
Although there is nothing new in it, I must take my 
chance of boring those who have studied the phenomena 
of floods in rivers, by giving here some facts which most 
people know, but which must be set forth as a preface to 
a consideration of subsequent details. Thus the characters 
of floods vary from the most erratic and incomprehensible 
phenomena in small rivers, to the grand uniformity with 
the seasons in great rivers, and between the extremes it is 
impossible to find any distinct boundary which may divide 
the simple from the complex. 
Every great river has hundreds of tributaries, in each of 
which the floods are subject to no known law, as every 
passing thunder-shower may gorge the smaller branches 
with floods, and every rain-storm will cause floods in some 
of the larger; but the parent rivers, like the Amazon, the 
Parana, the Nile, or the Ganges, rise inch by inch for 
months, keep stationary for awhile, and as slowly subside, 
There is a grandeur and solemnity about the floods of great 
rivers which have at all times impressed not only civilised 
observers, but even more so the timid, superstitious savages, 
who, looking at the yellow turbid waters steadily rising 
during parching hot weather and cloudless skies, and being 
unable to imagine the cause, satisfy their wonder by 
attributing the rising flood to the “ Water God,” who is 
pouring it out of caverns in the mountains. 
The simplest example of this phenomenon—that is, the 
effect of the erratic floods of all its tributaries on the 
flood of the parent river—may be studied inalarge lake, such 
as the Lake of Nicaragua, where I passed many days of 
my youth. Into this lake dozens of rivers enter, some 
