He was co-owner and editor of the Glasgow Courier; wrote in London on politics, geography, economics, and general literature; and founded a bank in Mauritius.
Although Macqueen had no academic education, professional training or qualifications, his amateur energy and enthusiasm, in several fields, made him a prominent, and controversial figure.
The Admiralty postal sailing brigs were considered to be slow and unreliable by the colonial community, so on his return to Glasgow in 1830 he started a campaign for a steamship mail service to the West Indies.
In 1840 the Admiralty awarded it a contract to deliver mail to the West Indian colonies, with the first departure from Falmouth, Cornwall, on 3 January 1842.
He died, aged 92, in poverty, and his 59 year old widow Jean was forced to survive on charitable handouts from fellows of the Royal Geographical Society.