1From Thomas Jefferson to F. Nichols, 19 September 1806 (Jefferson Papers)
Th: Jefferson presents his compliments to mr Nichols and his thanks for the copy of Playfair’s geometry he was so kind as to send him. he does not doubt it’s value from the known reputation of mr Playfair, and he cannot but applaud the zeal for promoting public utility which encounters the printing of such books, which tho’ of great value, are of slow sale. MoSHi : Bixby Collection.