After completing his education on the Continent of Europe, he obtained a clerkship in the War Office in 1857.
On his arrival in London Lord George Germain, secretary of state, appointed him to a clerkship in his office.
In 1756, immediately on his leaving school, he was appointed to a junior clerkship in the secretary of state's office by Henry Fox (afterwards Lord Holland), with whose family Dr Francis was at that time on intimate terms; and this post he retained under the succeeding administration.
In 1762 he was appointed to a principal clerkship in the war office, where he formed an intimate friendship with Christopher D'Oyly, the secretary of state's deputy, whose dismissal from office in 1772 was hotly resented by "Junius"; and in the same year he married Miss Macrabie, the daughter of a retired London merchant.
In 1589 he received the first substantial piece of patronage from his powerful kinsman, the reversion of the clerkship of the Star Chamber.