Here's a data point for you - Galton's Isochronic Passage Chart, showing the time in days to travel from London to the rest of the world, in 1881. (12 years aft

Here's a data point for you - Galton's Isochronic Passage Chart, showing the time in days to travel from London to the rest of the world, in 1881. (12 years after the Suez opened, and the map shows how useful that canal was.) Map at https://en.wikipedia.org/wiki/Isochrone_map https://en.wikipedia.org/wiki/Isochrone_map linking to https://en.wikipedia.org/wiki/Isochrone_map#/media/File:Isochronic_Passage_Chart_Francis_Galton_1881.jpg https://en.wikipedia.org/wiki/Isochrone_map#/media/File:Isoc... . Eastern Indian is 20-30 days. Batavia is about 30 days. Perth and Hong Kong are in the 30-40 day range. Sydney and most of the interior of Australia is in the 40+ day range, as is New Zealand's South Island. "It assumes that there are favourable travel conditions and that travel arrangements over land have been made in advance. It assumes travelling methods of the day within a reasonable cost." EDIT: https://archive.org/details/friendsreviewrel06lewi/page/702/mode/2up?q=%22London+to+Calcutta%22 https://archive.org/details/friendsreviewrel06lewi/page/702/... from 1853 lists routes from London to Calcutta ("Friends' review; a religious, literary and miscellaneous journal", p702): "The distance from London to Calcutta, by the Cape of Good Hope, is 15,000 miles requiring 150 days. With steam say 70 days." ["150 days" agrees with your "about half a year."] "The distance from London to Calcutta, by Cape Horn, is 21,500 miles requiring 215 days. With steam say 90 days." "From Liverpool to Calcutta, by Isthmus of Panama, 14,00 miles requiring 140 days. Steam, say 60 days." "London to Calcutta, overland route, five trans-shipments, 6,000 miles, 58 days" "Liverpool, New York, and Railway to San Francisco, two transhipments, 12,000 miles, 35 days." It's from a piece arguing for the usefulness of building a railway across the US (New York to San Francisco), to shorten the London/Calcutta route. That last route didn't exist until 1869, the same year the Suez Canal opened. EDIT #2: https://archive.org/details/sim_the-lancet_january-3-june-26-1852_1_1479-1504/page/384/mode/2up?q=%22London+to+Calcutta%22 https://archive.org/details/sim_the-lancet_january-3-june-26... has someone leaving London June 1817 and arriving Calcutta 2 December 1817, so about 5 1/2 months. (The Lancet January 3-June 26, 1852, p384, "Biographical Sketch of James Ranald Martin, Esq., F.R.S.") EDIT #3: The clipper ship Jane Pirie, built 1847, could do the round-trip in "eight months and a half ... the ordinary time occupied over the voyage being ten to eleven months." https://archive.org/details/sim_illustrated-london-news_1851-04-05_18_477/page/278 https://archive.org/details/sim_illustrated-london-news_1851... /mode/2up?q=%22London+to+Calcutta%22 ("Illustrated London News 1851-04-05: Vol 18 Iss 477"). As I understand it, clipper travel would have been fast and expensive.