He made a significant geological discovery in the 1850s when his tenant found fossilized leaves embedded among basalt lava on the Island of Mull.

He also helped to popularize ornithology and was one of the first to give a detailed account of the principles of bird flight in the hopes of advancing artificial aerial navigation (i.e. flying machines).

[2] By the time of his succession, Argyll had already obtained notice as a writer of pamphlets on the disruption of the Church of Scotland, which he strove to avert, and he rapidly became prominent on the Liberal side in parliamentary politics via the Peelite Conservative Party faction.

In William Ewart Gladstone's first government of 1868 to 1874, Argyll became Secretary of State for India, in which role his refusal to promise support against the Russians to the emir of Afghanistan helped lead to the Second Afghan War.

[citation needed] Argyll also played a key role in the establishment of the Royal Indian Engineering College which functioned from 1872 to 1906.

This college which was located on the Coopers Hill estate, near Egham was set up in order to train civil engineers for service in the Indian Public Works Department.

In 1871, while actually serving in the Cabinet, his son and heir, Lord Lorne, married one of Queen Victoria's daughters, Princess Louise, enhancing his status as a leading grandee.

[4] In 1886, he fully broke with Gladstone over the question of the prime minister's support for Irish Home Rule, although he did not join the Liberal Unionist Party, but pursued an independent course.

He did argue against the erosive capability of glaciers (1873) and was an important economist (1893) and institutionalist (1884a), in which latter capacity he was quite similar to his political opponent, Benjamin Disraeli.

In 1881, Argyll married Amelia Maria (born 1843), daughter of the Right Reverend Thomas Claughton, Bishop of St Albans, and widow of Augustus Anson.