Idaho semi-weekly world. [volume] (Idaho City, Idaho Territory) 1875-1908, 1888-04-24
RAINFALL ON HE PLAINS.
Some Interesting Statistics Showing That
1t Is slowly Increasing in Volume.

| Some Interesting Statistics Showing That
1t Is slowly Increasing in Volume.
Wheat growers and other large classes
| of citizens have been much interested in
! the repeated statements, made in the last
| few years, that the annual rainfall be-
tween the Mississippi river and the Rocky
mountains is slowly increasing The TACT,
| If it be a fact, has great agricultural i'm
portance The testimony offered in proof
of it, however, has, until recently, been
unsatisfactory, and has fallen short of
demonstration. Something more conclu-
sive is now adduced by Mark w. Har-
rington, editor of The American Meteor
| illogical Journal, In recent number OF
! that publication.
If chart be constructed on which
lines are drawn through places having the
| same annual RAINFALL these lines, in the
region under consideration, will be found
to run nearly parallel. The one along
which the precipitation is forty inches
passes near Montreal, Albany, the south
ern shore of the great lakes, the north
western Iowa and then southwark to the
Texas coast near Indianola. The line for
thirty inches runs near st. Paul, Mimi,
through eastern Nebraska, and central
Kansas and Texas. And twenty inches
fall along line starting in northern Min
nesota, curvng out beyond Bismarck, and
then aiming nearly straight for the upper
Rio Grande. AT Cheyenne the rainfall is
about eleven inches. Mr.. Harrington has
made a comparison between the position
Of these two periods thirty years
ebart, and finds a distinct westward
movement in some portions of
them. He uses Blodgett's and Denison's
data. Lorin Blodgetts collation. of rain
fall statistics for the United States which
came out in 1857, though now out of date,
is work of recognized value and covers
period of several years. Harrington, in
making an average from these figures,
thinks they may be said fairly to repre-
sent the situation in 1850. Denison is a
Denver physician who has written ex
tensively on climate, from n sanitary
point of view and has employed in, pre-
pairing his tables the signal service re-
ports of term of years, ending with 1888
and averaging about 1880 The method
employed by Mr.. Harrington and the
character of the work done by the authors
whom he cites justify much confidence in
the results attained in his inquiry.
1t appears from this comparison that in
the extreme northern part of Minnesota
the lines of equal rainfall have receded
eastward slightly. A more trifling move
ment, in the same direction, occurs in
southern Texas. Elsewhere there has
been progress toward the mountains, the
most marked change being between lati-
tude 40 and 45 dogs. Thus the twenty
five inch line has moved from the neigh
borhood Of st. Paul, out into Dakota,
being replaced by the thirty inch line. In
southern Dakota the twenty inch line has
advanced from the vicinity of Huron to-
ward Fort Bennett, upward of 1875 miles,
and is succeeded by the twenty-five inch
line. in Iowa and Minnesota the move
| ment is equivalent to about five miles q
year in thirty years; in Nebraska and
Kansas slightly less. Without entering
into any detailed explanations of the
phenomenon, Mr.. Harrington observes
that the increased rainfall occurs along
the line Of largest immigration to the
plains; and as that invasion is still going
on, on an enormous scale, it is hardly
safe to conclude that the attendant me-
neurological change will not continue even
| further-New York Tribune