360 KANSAS CITY REVIEW OF SCIENCE. 
Why, admitting the causes stated, did not the river reach the height of ’76 
or the greater height of ’51? 
Simply that none of the snow-water mingled with the flood just past. In 1876 
from thirty to forty per cent. of the snow that fell during the winter of 1875 and 
1876 and drained into the Upper Mississippi, mingled with that flood, hence high- 
er than the flood of 1880. Again it may be asked, why the flood so destructive 
above, did not reach the danger line by more than two feet in Lincoln and St. 
Charles counties? The answer is, the greater capacity of the river, which is 
from one and three-fourths to two and a fourth miles wide in St. Charles, while at 
places above it is not half that width. And to this fact may be attributed the 
breaking of the Sny Levee, avarice crowding it out when reserve room should be 
left for high water. 
Most persons interested in the Mississippi Valley are familiar with its present 
condition, but the physical changes are forgotten, if ever understood by the mass- 
es, and that the change is a matter of general interest, will justify giving some of 
its causes. Twenty-five years back, or in 1855, very little of the land draining 
into the Upper Mississippi was improved, say between three and five per cent. 
At that time the population of Iowa was very small; Minnesota and Wisconsin 
were almost a wilderness, and the dense forests of those States were unbroken ex- 
cept by the bridle or foot-path of the Indians and very few small clearings on the 
principal streams. The chief physical changes in the last twenty-five years are 
the gradual lowering of the high water, the lessening of malarial fevers and the 
climatic changes of warmer summers and colder winters. 
The change of temperature of seasons is generally admitted to be caused by 
the destruction and cutting and clearing of the forests. |The decrease of fevers 
is owing to the increased cultivation of the land, making it porous and absorb- 
ent, and the general drainage of the land as cultivated. 
The gradual lowering of maximum high water embodies several causes, the 
chief of which is the cutting of the timber in the heavy snow-beltan the States of 
Iowa, Minnesota and Wisconsin, that drains into the Mississippi river. When 
these forests, that have furnished lumber for the valley and country west of the 
river for the last twenty years, were intact, the heavy snows were shaded and did 
not thaw until the spring heat got so strong that nearly all the snow was changed 
to water in a few days—and swelling the streams and rivers so rapidly, that when 
emptying into the Mississippi they had the appearance of crested waves. Heavy 
snows rapidly changed into water, and all, centering in the one channel, resulted 
in high water, and then such high waters reached the wide lower plateaus along 
the river, when the season was very wet, or in conjunction with very heavy rains, 
as happened at intervals of fifteen or twenty years, resulted in overflow. The 
doing away in chief with this cause has been the work of the lumberman 
and pioneer for the last twenty-five years, as slowly but surely they have been 
cutting away the great pineries at a rate varying from one to five per cent. a year, 
so that at this time not more than twenty-five per cent. of the original forest re- 
