But Polk County was not exactly north of Warren County ; hence in redefining the boundaries of Dallas, Polk, and Jasper counties the first two were shifted each one range farther west while the western boundary of Jasper was moved one range in the same direction.

These shifts brought Polk County directly north of Warren from which it gained one tier of townships.

Fort Des Moines was now near the center of Polk and secured the county-seat.

And so it may be said that the boundaries of Jasper County were redefined and the county enlarged by the act of January 17, 1846, merely to accommodate Polk County and more especially the boomers of Fort Des Moines.

The boundaries of Jasper have not been altered since the date last mentioned.