58 Trans. Acad. Sci. of St. Louis. 
time. As civilization grows or as the civilized population 
increases, wider knowledge of the geography and better maps 
become necessary to meet the needs of new settlement or of 
commerce ; and, when population becomes dense, better and 
better maps are constantly demanded to answer the require- 
ments of a great traffic, for purposes of construction and 
improvement and for the exact establishment of property 
lines which the enhanced value of real estate calls for. 
Hence, the mapping of an area is necessarily a progressive 
work; there is an evolution of cartography as of other 
objects, natural and cultural. The earliest charts are the prod- 
ucts of exploration; rudé sketches showing mere outlines 
and these defined with only a slight approach to accuracy. 
A few astronomically determined points, roughly determined 
at that, constitute the principal data as to location, supple- 
mented, perhaps, by a meander line run down some river, in 
a boat, with hand compass bearings and estimated distances. 
As other explorations are made additional points are deter- 
mined, lines of travel are meandered out, corrections are 
made of errors in former locations and, by degrees, a fairly 
reliable diagram of the area is produced. As the country 
becomes populated, surveys for political divisions and for 
cadastral divisions are inaugurated and, from these, additional 
facts are collected. Finally, and it is deplorable that it 
should seemingly be necessarily at so late a stage, triangula- 
tion is extended over the area, topographic mapping 18 
_ prosecuted and detailed maps of various kinds to suit the dif- 
ferent needs are produced. In nearly all civilized countries 
detailed and accurate maps are now constructed of different 
portions, but it would be hazardous to assert, at present, that 
of any one area the final map has been produced. 
Missouri has had, like other countries, her succession of eX- 
plorations and surveys and resultant maps, but she is still far 
from having reached the final stage. It is the purpose of this 
article to display the status of such work at the present time, 
to briefly sketch the history of mapping as affecting Missouri 
and to indicate the probable lines of future growth. 
The first maps including the area of Missouri are necessar- 
ily those rough diagrams of the early explorers which repre- 
