Mayflower 400: the science of sailing across the ocean in 1620

Jonathan Ridley:

It is July 1620 in Southampton, England. Arriving into port is the Speedwell, a ship carrying a small religious group from the Netherlands. Anchored just off of the west quay of the town is the Mayflower, a larger ship with more passengers aboard, which is loading for a transatlantic voyage with the Speedwell. The passengers have permission and funding to start a trading settlement in the Colony of Virginia (which at the time extended far further than the modern state of Virginia), under the control of the Virginia Company.

Despite the historical significance of the Mayflower, we know very little about the ship and its voyage. We only know its name from a document written three years after the voyage. At the time the Mayflower was not notable or special and – because some of the passengers faced persecution for their religious activities – they probably kept a low profile.

Evidence suggests that it was “burden about nine score” or 180 tons. “Burden” was a term for cargo capacity, while a “tun” was a large cask of wine. The ship could therefore carry the equivalent of 180 tuns of wine.

There are unfortunately no illustrations or plans of The Mayflower from the time, so we don’t even know for certain what the ship looked like. We do know, however, that ships around this time were built to a series of similar rules (outlined in Swedish shipbuilder Fredrik Henrik af Chapman’s Architectura Navalis Mercatoria, published in 1768). We can therefore begin to estimate the proportions for the cargo carried, but with a caution that the rules varied between shipwrights, with many details not recorded and drawings not made.