33 
Rocky Mountain regions of the West. A case in point occurred during the 
past summer in the latter part of July over an area of some six or eight 
square miles along the divide between the basins of Indian Kentucky and 
Indian creeks and their tributaries, in eastern Jefferson and western 
Switzerland counties of this State. The rainfall in this case was un- 
precedented for the region. On one border of the given area a government 
rain gauge, kept by J. R. Shaw, Jr., was filled to the brim, the measure- 
ment amounting to three and one-half inches, and then ran over for an 
unknown period. Afterward the gauge was emptied and received one and 
one-half inches more, making at the least five inches, and probably mmch 
more, in the period of two hours during which the rain fell. Other and 
more reliable measurements in locations more nearly the center of the 
storm area were made and a precipitation of at least ten inches in the 
two-hour period were recorded. 
The conditions producing this exceptional and very destructive rain- 
storm were as follows: ‘The region to the west and southwest of the 
storm-swept region is one ot the roughest topographically in southern In- 
Giana. The whole area for ten or twelve miles in this direction forms 
the basin of Indian Kentucky Creek and tributaries, and the hills rise 
in many instances 400 to 450 feet above the valleys, and the slopes are 
yery steep. From the whole basin the forests have been almost entirely 
removed. On the day referred to the temperature was unusually high, 
some thermometers within the area registering 102 degrees in the shade. 
There was no movement of the air until early in the afternoon, when a 
gentle southwest wind arose, and this caused the highly-heated air of the 
whole region to move northeastward. The valley of Brushy-fork Creek, 
one of the principal tributaries of Indian Kentucky Creek, became the 
center of the air movement. About three in the afternoon a cloud began 
to form above the divide and around the head of the valley of Brushy-fork 
Oreek. The highly-heated air ascended very rapidly on reaching the divide, 
and the consequent rapid cooling of the air by expansion caused an equally 
rapid condensation of the moisture of the air. The cloud increased in 
volume with very great swiftness, and the rain fell in torrents, first over 
a very limited area and then over a wider region. The center of the storm, 
however, instead of moving, as is usually the case, remained almost sta- 
tionary for a period of two hours. During this time the winds from al- 
most the entire surrounding region moved slowly towards the now en- 
larged area of precipitation. There were few if any clouds outside of 
