During the Seven Years' War, British militia took blankets from their smallpox hospital and gave them as gifts to two neutral Lenape Indian dignitaries during a peace settlement negotiation, according to the entry in the Captain's ledger, "To convey the Smallpox to the Indians". In the following weeks, the high commander of the British forces in North America conspired with his Colonel to "Extirpate this Execreble Race" of Native Americans, writing, "Could it not be contrived to send the small pox among the disaffected tribes of Indians? We must on this occasion use every stratagem in our power to reduce them." His Colonel agreed to try. Most scholars have asserted that the 1837 Great Plains smallpox epidemic was "started among the tribes of the upper Missouri River by failure to quarantine steamboats on the river", and Captain Pratt of the "St. Peter" "was guilty of contributing to the deaths of thousands of innocent people. The law calls his offense criminal negligence. Yet in light of all the deaths, the almost complete annihilation of the Mandans, and the terrible suffering the region endured, the label criminal negligence is benign, hardly befitting an action that had such horrendous consequences." However, some sources attribute the 1836–40 epidemic to the deliberate communication of smallpox to Native Americans, with historian Ann F. Ramenofsky writing, ""Variola Major" can be transmitted through contaminated articles such as clothing or blankets. In the nineteenth century, the U. S. Army sent contaminated blankets to Native Americans, especially Plains groups, to control the Indian problem." Well into the 20th century, deliberate infection attacks continued as Brazilian settlers and miners transported infections intentionally to the native groups whose lands they coveted."