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The Philadelphia Commercial Museum
Fig. 66. Commerce of the United States since 1830. The Sum of Annual Exports and Imports. Values are given in Millions of Dollars
Such a chart as this is worse than none. There is no scale
in either direction. The block for 1830 is drawn with a
larger area than the block for 1840 which represents a
larger quantity. Compare with Fig. 67 and Fig. 68
