First I have to say that most ships in that time period were not meant specifically to go fast apart from some warships. Much like in modernity the goal of many ocean-going vessels is to transport goods with passengers being a secondary thought. Also, the real advancements in terms of speed did not start occurring until the 19th century with the introduction of clippers(S.S. Baltimore) and the famous speed runs were the china to London tea race and the eastern to western united states seaboards via cape horn. Also, sailing vessels(windjammers) were built during the 20th century and were not totally retired until the 1930-1940’s.

The most important advancement in terms of speed as accurate navigation and cartography. The invention of mechanical watches allowed sailors to have an accurate understanding of longitude which means that they were able to better understand their location on a map. As the centuries rolled by more and more seaman better understood the world currents as well as the trade winds marking them on maps which aided them in planning routes. If you want to see these charts the David Rumsey map collection is a great place to start!

Ship design changed as well, their lines became longer and more streamlined. Sail ships can only go as fast as the wind and depend on the amount of canvas so the elongation was a consequence of trying to add in more masts to the normal fully rigged ship of three and later four masts. The Dutch and British East-Indians were rigged in a way that reduced the number of men needed to operate the vessel and decreased the amount of weight in terms of provisions for cross-oceanic trade. Speed didn't become a factor until the creation of the united states and the Napoleonic wars. Americans began to see that even larger ships (that is, longer in relation to breadth) could carry more sail and thereby gain speed and the ability to sail well under more types of winds. For perishable cargoes speed meant that these fast ships reached British and European markets before those of their competitors and with a product in better condition. The Mayflower had taken 66 days to cross the Atlantic in 1620. The Black Ball Lines nine-year average as of 1825 was 23 days from England the US.

To put the speed of these clippers into perspective the clipper Sovereign of the Sea could max out at 22 knots. The battleship USS Texas could only max out at 21.5 knots, and the average speed of Liberty cargo ships when in convoy was 9 knots. Steam propulsion was not adopted to increase speed but reliability of speed.

Hope this helps!

(please ask about whaling vessels, my degree is next to useless if you don't)

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