Winslow —The Mapping of Missoure. 81 
sissippi river; thence down and following the course of the 
Mississippi river, in the middle of the main channel thereof, 
to the place of beginning.”’ 
The boundary line from the mouth of the Kansas river to 
the northwestern corner, and thence east to the Des Moines 
river, is the same as the old Indian boundary line above 
described as surveyed in 1816. This was apparently accepted 
as a correctly located State line up to the time of the Platte 
purchase, in 1836. Immediately after this, however, during 
the summer of 1837, a new survey of this line was made, in 
accordance with an act of the General Assembly of Missouri. 
This line was surveyed by Joseph C. Brown. It began at the 
rapids on the Des Moines river on the old Indian line. The 
longitude of this point was calculated from Elliott’s determi- 
nations, at the mouth of the Ohio, and from the measurements 
of the Land Office survey, and was determined to be 91° 46’ 
40” west of Greenwich. The latitude was determined by 
astronomical observatious to be 40° 44’ 6” north. Several 
latitude determinations were made along the line and observ- 
ations for the variation of the compass were frequently 
taken; a compass was used in the work, and its bearings were 
checked by back sights. The total length of the line from 
the Des Moines to the Missouri river as measured, was 
203 miles and 33 chains. The longitude of the N. W. corner 
was calculated to be 95° 39’ 13” and the latitude, from observ- 
ations about 40° 44’. 
The location of this survey seems, however, not to have 
been acceptable to the State of Iowa and more or less liti- 
gation arose therefrom. Hence in 1850, a new survey was 
ordered by the Supreme Court of the United States.* The 
starting point taken was Sullivan’s N. W. corner, established 
by the Survey ot 1816.¢ The latitude of this point was 
determined to be 40° 34’ 40” 3 N.; the longitude calculated 
from the Land Office maps was determined to be 94° 30’ W. 
of Greenwich. The line was run due west on a parallel for 
a distance of 61 miles and 61 chains to the Missouri river; 
* See Howard’s Report, Vol. 10. 
+ The surveyor for Missouri was R. Walker 
Sige , and the one for Iowa was 
