Walker's Statistical Atlas of the United States. 165 
is by far the best of its kind we have yet seen of the country. 
Twenty-one drainage areas are denoted (each accompanied 
with certain statistical information), the whole naturally thrown 
into groups or systems, only one of which we will here notice. 
According to this map, the Mississippi basin embraces about 
1,258,000 square miles of our domain. A small portion of 
the Missouri basin extends into British America, perhaps about 
22,000 to 25,000 square miles. Ifthis be added, the area of the 
whole basin will be about 1,270,000 to 1,278, 000 square miles. 
This is somewhat larger than the area “usually given by the 
authorities most often consulted. The figures from the Report 
7 the Physics and Hydraulics of the Mississippi River, by 
the U. S. Topographical Engineers some years ago. are 1 2 000 
square miles, while the various works on geography and 
physical geography usually give it from 1,200, 000 to 1 ,250,000. 
This “Great Central Valley,” as a geogra phical feature of 
the continent, is, however, much larger, including on its 
southern borders portions which drain directly into the Gulf, 
and northward aie insensibly into the great areas which 
drain into Hudson's Bay and even into the Arctic Oce 
The Mississippi basin, according to this map, eontained at the 
last census, a population of about 16, 292,000, exclusive of 
“Indians not taxed.” The whole basin is divided into six 
parts,—the Lower Mississippi, Upper shame Ay Ohio, Mis- 
souri, Arkansas and Red River basins. The basin of the Ohio 
has naturally the greatest population. Bomewhae almond- 
shaped in outline, or like a leaf, veined with large rivers, its 
point reaching to New York, it was the natural channel down 
which emigration flowed westward to the greater valleys be- 
yond. Its genial sinaate fertile soil, its prairies here, and 
wealth of timber-land there, have so attracted the settler that it 
will probably long remain the most densely populated basin of 
the system. The “center-of population” of the nation passed 
into it about forty years ago. Another century will probably 
find it still there. The area is given as 207,000 square miles 
(the Report on Hydraulics, &c., already cited, stating it as 
214,000), or about one-sixth of the whole Mississippi basin, and 
= Cee 7,800,000, is nearly half of the population of the 
whole basin. 
mate already given for that part outside the United States, it 
would give the entire Missouri basin an area of about 550,000 
to 553, 000 square miles. The Engineers’ report previously 
cited estimates it at 518,000. 
