He moved from academia to important positions in business and industry, including serving as Chairman of the British Overseas Airways Corporation.

He was knighted in 1928, made KCVO in 1944, GCVO in 1957 and Member of the Order of the Companions of Honour (CH) in 1967.

[2] His candidacy citation read: Distinguished for his investigations in physical and mineralogical chemistry, including electrical conductivity, ionisation, and electrolytic equilibria in aqueous and non-aqueous solutions.

Has greatly contributed by his own work and that of his pupils to the building up of a notable school of physico-chemical research at Oxford.

Hartley was married in 1906 to Gertrude, eldest daughter of Arthur Lionel Smith, who was later Master of Balliol College.