dent spirit, will bring on
disease, and, in six or eight months, great mortality.... I believe more
Indians might be killed with the expense of $100,000 in this way, than
$1,000,000 expended in the support of armies to go against them."[43]

Fortunately, wiser counsels than either of these prevailed to control
the Indians: the control of the fur trade was necessary. It was felt,
and rightly, that much of the trouble in the West was due to the
power of the British traders. Accordingly, by an act of Congress of
April 29, 1816, it was provided that "licenses to trade with the Indians
within the territorial limits of the United States shall not be granted
to any but citizens of the United States, unless by the express
direction of the President of the United States, and upon such terms and
conditions as the public interest may, in his opinion, require." To
carry this act into effect the president was authorized to call upon the
military force.[44]

This legislation was most opportune, since by the commercial convention
of October 20, 1818, the northern boundary was definitely agreed upon as
the forty-ninth parallel westward from the Lake of the Woods to the
Rocky Mountains.[45] Ever since the negotiators of the Treaty of Paris
of 1783 had inserted a geographical impossibility by declaring that the
boundary should extend due west from the Lake of the Woods to the
Mississippi, there had existed a vagueness as to where the actual line
should be drawn.[46] In 1806 the British traders thought it would be run
from the lake to the source of the river;[47] and as late as 1818
Benjamin O'Fallon wrote from Prairie du Chien that Robert Dickson "is
directed to build a fort on the highest land between Lac du Travers and
Red river, which he supposes will be the established line between the
two countries."[48] But with the boundary now defined, the area where
the trade laws were to be enforced was evident.

The method of Indian trade by foreigners was to be supplanted by
an extension of the United States trading house system. This was a group
of trading houses, conducted by the government, where the Indians could
exchange their furs for goods at cost price and thus avoid both the
deceit and whiskey of the private merchant, although they were often
willing to submit to the one for the sake of the other.[49] As early as
1805 Pike had promised the Indians, in council assembled, that the
government intended to build a trading house at the m