The Columbian. [volume] (Bloomsburg, Pa.) 1866-1910, 1883-12-14
The Flow OF Rivers.

As we have already had occasion to
state, the changes which occur from day
to day or from yearto year in the flow
of American rivers, especially in the
smaller streams, are rarely recorded.
the daily condition of the water in the
Mississippi and the Ohio at different
points is taken and published by the
Government Weather Bureau, but no
attention is paid to the stage of water
in less important streams. 1t Is noticed
by persons living along many of our
rivers, or navigating their waters, that
they have gradually undergone changes
of habit within the memory of the pre-
sent generation of men. Men not yet
old have seen little streams completely
dry during long periods of every year,
which when they were boys ran freely
and copiously throughout the year.
Rocks and sand bars have appeared in
rivers which not many years ago were
clear OF all Instructions A severe
summer rainfall is often followed by
quick rush of water down the bed of
the empty stream, where formerly
similar storm did not make itself appa-
rent in the flow of water, so gradually
did it find its way to the channel.
Springs are certainly lower everywhere
during the summer than they were a
century ago, and crops of all kinds feel
the effect of summer droughts more
seriously than formerly.
Such changes in the condition of
rivers and in the water supply of
springs are fully understood in Europe,
where such subjects have long received
careful attention, and such huvial
changes have been recorded, In this
country, people have been satisfied to
see their streams grow year after year
more uncertain and less useful, and
their farms dry up, without making any
effort to inquire into the causes which
were operating these changes, much less
to take any decisive steps to prevent
them, or even to preserve any record OF
their occurrence and extent.
The student therefore, who attempts
to reach accurate information in regard
to the causes which have operated a
change in the condition of any stream,
is met at the outset with serious diff
culties. General information is abun-
dant showing that great changes have
occurred in the flow of nearly all our
rivers where the forest has been re-
moved from their sources. But in order
to prove beyond any question of donbt
that the destruction of forests has in
fuenced the flow of any particular
stream, it is necessary to know the
amount and distribution of the rainfall
over its watershed-for it must not be
forgotten that there are everywhere
very considerable local variations in the
rainfall of any great region--the ex-
tent of forest cleared at different tim, 8
from ITS watershed, and the condition
of the river itself, day by day, both be-
fore and after this removal of the for
est had taken place. These facts being
known, il will be possible TO show in a
thoroughly scientific manner the influ.
ence of tue destruction of particular
forest upon the flow of a particular
stream. Until such facts can be deter
mined, any statement in regard to any
rivers, although based upon the con-
scientious observations of intelligent
men, may be subject to doubt aud open
TO criticism. Unrecorled observations
are not science aud scieneoalone can be
trusted to demonstrate beyond question