Hume seems to have made a very favourable impression on General St.Clair, as he did upon every one with whom he came into personal contact; for, being charged with a mission to the court of Turin, in 1748, the General insisted upon the appointment of Hume as his secretary.

He further made him one of his aides-de-camp; so that the philosopher was obliged to encase his more than portly, and by no means elegant, figure in a military uniform.

Lord Charlemont, who met him at Turin, says he was "disguised in scarlet," and that he wore his uniform "like a grocer of the train-bands." Hume, always ready for a joke at his own expense, tells of the considerate kindness with which, at a reception at Vienna, the Empress-dowager released him and his friends from the necessity of walking backwards.

"We esteemed ourselves very much obliged to her for this attention, especially my companions, who were desperately afraid of my falling on them and crushing them." Notwithstanding the many attractions of this appointment, Hume writes that he leaves home "with infinite regret, where I had treasured up stores of study and plans of thinking for many years;" and his only consolation is that the opportunity of becoming conversant with state affairs may be profitable:-- "I shall have an opportunity of seeing courts and camps: and if I can afterward be so happy as to attain leisure and other opportunities, this knowledge may even turn to account to me as a man of letters, which I confess has always been the sole object of my ambition.

I have long had an intention, in my riper years, of composing some history; and I question not but some greater experience in the operations of the field and the intrigues of the cabinet will be requisite, in order to enable me to speak with judgment on these subjects." Hume returned to London in 1749, and, during his stay there, his mother died, to his heartfelt sorrow.