In the Georgia Gazzette, of Savannah, October 11, 1769, appeared an item dated February 27th of that year, apparently copied from a New York newspaper, announcing the arrival of Adair in New York and saying that "he intends to print the Essays". The care with which the book is printed indicates that he gave it personal supervision through the press. From the dedication it is evident that he had the friendship of the noted Indian traders, Col. George Galphin and Col. George Croghan (with the former of whom he may for a time have been in partnership) and Sir William Johnson; and from various references it is certain that he was highly respected by those who knew him. Logan credits him with the quick penetration of the Indian audacity, cool self-possession, and great powers of endurance, and Volwiler says that he was one of the few men of ability who personally embarked in the Indian trade.
[J. H. Logan, A Hist. of the Upper Country of SC (1859); John Thos. Lee, letter in the Nation Aug 27, 1914; brief references in A.T. Volwriter, Geo. Croghan and the Westward Movement, 1741-1782 (1926) )