The character of Armstrong seems, on the whole, to have been of an amiable, though somewhat splenetic cast. By his friends, among whom he numbered some of the ablest and worthiest men of his time — Thomson, Granger, Theobald, Birch, Mead, Sir John Pringle, &c. he was much respected and esteemed. Several of them have borne strong testimony to the goodness of his heart, and general sincerity of his conduct. — He was blunt in his manners, and not very choice in his conversational language; but these asperities were quickly forgot in the liveliness of observation and dry humour with which they were accompanied. He is said to have been indolent and inactive, and fonder, at all times, of making one of a social party of literary friends, than of attending to serious occupation; and to this, perhaps as much as to that "distempered excess of sensibility," of which he talks in his Commentaries, we may ascribe the little success he experienced in his profession.