•262 
THE MIDDLE LIAS OF NORTHAMPTONSHIRE. 
Nen valley would care to be entirely relieved of floods ; they 
would prefer to have the water, if they could only have it at 
suitable times and get rid of it a little sooner, because of 
the fine silt which it brings, and which renders ordinary 
manuring unnecessary. Fanners are never likely to secure 
all these advantages, but some of them they might, providing 
they had somewhere to drain into ; this the water scheme 
under consideration provides. 
There are many causes tending to produce floods, and the 
relative amount of importance attached to any one of them 
is somewhat a matter of individual opinion. I have placed 
below the commonly-assigned reasons for recent heavy floods 
in the Midland counties in the order of their importance, 
according to my own belief:— 
1. —Excessive Rainfall. 
2. —Agricultural Drainage. 
3. —Blocking-up of Streams. 
4. —Artificial Obstructions, such as Mills, Railway Banks, 
Bridges, &c. 
1.—Excessive Rainfall. —That the rainfall for a number 
of years previous to 1883 was excessive is, I take it, an 
incontrovertible fact. The wet period I refer to extended 
from 1872 to 1883, twelve years; and from particulars fur¬ 
nished me by Mr. F. Law, for Northampton, I find that the 
average rainfall for the last nineteen years, including, of 
course, the wet period, is almost exactly 25 inches, whereas 
the average for the wet period was 27J inches, and the 
average of the dry period, that is three years previous to 
1872 and four years since 1883, only 21 inches, showing a 
difference of 6J inches between the wet and dry years. The 
lowest yearly average is for 1870 (16*19 in.), and the highest 
is for 1872 (33*15in.), a difference, it will be seen, of 16*96 
inches. Three other years, 1875, 1880, 1882, gave averages 
nearly double of the minimum. It cannot be said that 
33 inches is an excessive rainfall, except by comparison with 
drier years, and had the rain been more evenly distributed 
over the year very little damage would have resulted. 
So far as my experience enables me to judge, I should 
say that it almost invariably happens that the excess of rain, 
above the average for the district, is due to heavy falls in a 
short period; and these are particularly liable to cause floods, 
for much of the water will run over the surface of the 
ground even in well drained districts, and the floods very 
rapidly follow the rain. These heavy falls not unfrequently 
occur in the summer time, during thunderstorms. 
