[1] He entered the Royal Navy, but at the end of two years quit it for the British East India Company's military service, and in 1842 obtained a commission in the Bengal Light Cavalry.

[1] In 1857 he was appointed attaché to Lord Elgin's mission to East Asia, was present at the taking of Canton (Guangzhou) during the Second Opium War, and in 1858 brought home the Treaty of Yedo.

After three weeks, the negotiations for their release were successful, but they had only been liberated ten minutes when orders were received from the Xianfeng Emperor, who was then taking shelter in the Chengde Summer Palace, for their immediate execution.

During his governorship the House of Keys was transformed into an elective assembly, the first railway line was opened, and the influx of tourists began to bring fresh prosperity to the island.

The Boers were at the same time striving to frustrate Cecil Rhodes's schemes of northern expansion and planning to occupy Mashonaland, to secure control of Swaziland and Zululand and to acquire the adjacent lands up to the ocean.

Loch firmly supported Rhodes, and, by informing President Paul Kruger that troops would be sent to prevent any invasion of territory under British protection, he effectually crushed the Banyailand trek across the Limpopo River (1890–1891).

Loch, however, with the approval of the imperial government, concluded in July–August 1890 a convention with President Kruger respecting Swaziland, by which, while the Boers withdrew all claims to territory north of the Transvaal, they were granted an outlet to the sea at Kosi Bay on condition that the republic entered the South African Customs Union.

This convention was concluded after negotiations conducted with President Kruger by Jan Hendrik Hofmeyr on behalf of the high commissioner, and was made at a time when the British and Bond parties in Cape Colony were working in harmony.

[3] The Transvaal did not fulfil the necessary conditions, and in view of an increasingly hostile attitude from Pretoria administration Loch became a strong advocate of annexation of the territory east of Swaziland, through which the Boer railway would have to pass to the sea.