IT 148 [Treaty 61] is a manuscript original of the Robinson-Huron Treaty signed at Sault Ste. Marie, Province of Canada, on September 9, 1850 by the Hon. William B. Robinson representing the Crown, and the chiefs and representatives of the Ojibway. The Robinson-Huron Treaty purchased the Aboriginal interests to lands and resources north of Lake Huron to the boundary between lands controlled by the Hudson's Bay Company and those controlled by the Province of Canada. The Robinson-Huron Treaty, and its companion IT 147, the Robinson-Superior, are unique. The land set aside for reserves was not part of the surrender. The annuities provision contained an "escalator" clause, promising a payment increase should the surrendered territory become more productive.
IT 148 Source