On returning from the Grisons in 1753 de Salis was sent with two of his brothers, Charles (1736–1781) and Peter (1738–1807), to Eton (he left c1757), after which he went up to Queen's College, Oxford, BA (1760), MA, DD (1777).
His proposers were: Lyttelton; Jeremiah Milles (c 1714 – 1784); Le Despencer; Anthony Shepherd (1721–1796); John Hunter; Robert Mylne (1734–1811); Erasmus Saunders (d. 1775); Samuel Wegg (1723–1802).
[6] De Salis's parents appointed him Game keeper of and for their said manor of Dally otherwise Dawley, near Hayes, Middlesex, from 13 June 1775.
[7] In a letter to his father in Harley street, dated Oxford 24 September 1771 he describes 'Lord le Despencer's Festival at West-Wycombe': He married at St. Antholin, 17 November 1775, Miss Julia Henrietta "Harriet" Blosset from a well-connected huguenot family (d. 18 January 1819, at Hanwell), second daughter and co-heir of Solomon Stephen Blosset of Dublin & Meath (grandson of Salomon Blosset de Loche), by his wife Elizabeth Dorothy Le Coq St. Leger, from Trunkwell House at Shinfield (now Beech Hill) in Berkshire.
Harriet Blosset was the girl who in 1768 had been led to believe by Sir Joseph Banks (1743–1820) that he would marry her on his return from his journey with Cook on the Endeavour.
They returned in June 1771 but Banks's previous affections had been irrevocably changed by his 3 years of living with the Tahitian natives; compensation was paid.
Having died on the same day as her paternal grandmother she was buried simultaneously with her in the family vault at Harlington-under-Heathrow, Middlesex, a church that is both close to Heathrow airport and clearly visible from the M4.