Winslow —The Mapping of Missouri. 99 
Reference to surveys and original maps in the State, would 
not be complete were mention omitted of all the various 
railway surveys and the resultant maps. These have fur- 
nished a great amount of data and, were all the results of such 
surveys available we should have material for the construction 
of topographic maps of considerable portions of the State. 
As it is their locations of constructed lines are valuable base — 
lines for all operations of geographic surveying and their pro- — 
files are invaluable for determinations of altitude. 
Innumerable maps have been constructed of the State of 
which no mention has been made here. The reason for this 
is that these maps are compiled and are not prepared from 
new and original surveys. All of what is entitled to the name 
of original geographic work, in an extended sense, is referred 
to here. Many excellent and serviceable maps have been 
compiled from the Land Office plats, supplemented by rail- 
way maps. Many county atlases have been similarly pre- 
pared. To these, county roads, post-offices, school-houses, 
churches, boundaries and other such features are added from 
county records and from observations on the ground. 
