Why Did People Travel on Water?
Water travel has a long tradition because it is almost always more efficient than land travel. That sounds counterintuitive. After all, we’re terrestrial mammals, so how could water make a better medium of travel than good old terra firma? That’s where technology enters the picture.
We can walk much more efficiently than we can swim, but boats change the entire scenario. A small boat can carry way more than a human, or even other terrestrial transport options like carts or pack animals, can. Carts require roads, and animals need to be fed. Meanwhile, water can support a vast amount of weight, and with a hydrodynamic prow, it’s relatively low on drag.
That’s why people historically traveled by water whenever it was an option. Whether they were trading, settling, or exploring, a ship always beat walking. Even prodigious road builders like Rome and China preferred to use water when it was available, so you can imagine how less technologically advanced cultures leapt at the chance to use these naturally occurring highways.
That’s not to say people have always traveled across water the same way. Technology, environment, and maritime traditions all had major effects on how people go voyaging, to say nothing of economic or military motivations. Even so, there were a few commonalities we can examine that will help you portray water travel in whatever worlds you dream up.
More than anything else, the type of waterway was a major factor in determining what kind of voyages people undertook. Rivers acted as natural roads and were so good at facilitating trade that humans have long been digging their own. Perhaps the most famous is the Grand Canal, built and expanded over several centuries by multiple Chinese dynasties.
Large bodies of water like lakes or inland seas were also great facilitators of trade and travel. The Mediterranean, Black, and Caspian Seas were all large enough that a great variety of people could live around them, but small enough that crossing them was relatively easy. This created vast networks of interconnected cultures, all brought together by the water they traveled on. Under the right circumstances, these seas facilitated the growth of empires as well. There’s a reason the Romans expanded primarily around the Mediterranean: it made their vast territory far easier to administer.
Finally, we come to large oceans like the Atlantic and Pacific. The Pacific Ocean is dotted with islands, which encouraged people to venture out and explore, as we can see in the Polynesian Triangle. As civilization in the Mediterranean Basin was still recovering from the Bronze Age collapse, the great Polynesian Wayfinders were sailing out from Asia as far north as Hawaii and as far east as Rapa Nui.*
On the other hand, oceans without a lot of islands didn’t inspire much beyond coastal travel. Crossing that much water was extremely difficult and didn’t offer any obvious rewards. This is a big part of why the Vikings reached North America long before Columbus came along. The Vikings island-hopped across the North Atlantic, so they could make the journey in simpler ships with less risk of death. Meanwhile, the Spanish Crown only sent expeditions westward once they had advanced ships like the carrack and caravel, plus the financial incentive of Indian* spices.
Wind and weather also has a major impact on water travel. Many parts of the world have seasonal storms that make voyages hazardous, so all ancient voyages were conducted during more pleasant times of year. In the centuries of Classical antiquity, it was common for Mediterranean ports to shut down for half the year to ride out the storms, then break into a frenzy of activity during viable shipping months.
Meanwhile, the direction of winds and currents created “uphill” and “downhill” routes, even across flat waterways. If the wind normally blew south, then southern travel would be relatively easy, but return journeys would be difficult and time-consuming. Fortunately, winds often switch directions depending on the season. In the Indian Ocean, northeast summer winds brought Egyptian and later Roman ships to the Indian subcontinent, while southwest winter winds sent them back again. The timing of these wind changes was critical, so aspiring navigators had to study up.
Modes of Propulsion
No matter if your characters travel on rivers, lakes, or oceans, their crafts will need some method of getting from Point A to Point B. Propulsion options were limited in a world without engines, but that doesn’t mean ancient mariners were completely without choice. Let’s look at our three main types.
Human muscles predate even the earliest technology, and oars* let us use those muscles to move boats around. In a world without engines, almost all watercraft needed to be row-able in some capacity as a backup, but plenty of vessels got by just fine with oars as their primary source of power.
The most obvious example were small boats like canoes or the conveniently titled rowboat. These little vessels were usually designed either for short trips or to be operated inland where travelers couldn’t count on wind. It was relatively easy for a single person to row themself along, though it could get tiring over long distance or against stiff currents. In shallow water, travelers sometimes used a long pole to push the boat along instead.
But it wasn’t just small craft that relied on oar power. Some of history’s most famous warships were propelled by oars, from the galley to the iconic trireme. Why warships specifically? Because oars provided speed and precision over short distances, exactly what ancient admirals needed. These ships had hundreds of rowers arranged in multiple banks, and the fastest triremes could reach about 11.5 knots* for brief sprints. That was blazing fast compared to other ships of the day, and it gave captains a great excuse to shout “ramming speed!”
In addition to speed, oars also offered reliability. There’s no risk of the wind dying at a critical moment in the battle and leaving the ship stranded. The great cost was efficiency. Large ships took a lot of rowers, about 170 for a good-sized trireme, more than ¾ of the crew. That many people required a lot of food, especially when they were doing the hard work of rowing, and yet because there were so many of them, there wasn’t much room on board for anything else.
That’s why larger rowing vessels tended to be very short ranged, and they were rarely used for trading or commerce. The trireme was a bit extreme in this regard, but even later ships like the galley were clearly designed to be short-range warships.
The problem with rowing was that it took a lot of work to move a ship on muscle power. Why not let the wind do the work instead? Okay, sailing was also a lot of work, and we’re getting to that, but the point stands: sails were vastly more efficient over long distances than oars.
This was true even at lower tech levels. Rowers could produce greater bursts of speed than sails, but even the fittest humans would tire eventually; meanwhile, the wind kept on blowing. Sails also took up far less room than rowers, which meant more space for passengers and trade goods. Nearly all merchant ships of Classical antiquity were sail powered, and that’s when sail technology was still in its infancy.
At higher tech levels, the advantages of sails became even more pronounced. Sail power scaled up a lot further than oars, which meant much larger ships. Moving a ship the size of HMS Victory with oars would have been a nightmare, but sails got the job done just fine. Sails also meant more room for cannons, which is why we see a sharp drop off in oared warships after the introduction of gunpowder.*
The downside to sailing was the same thing that gives it such an edge: wind power. Most immediately, winds didn’t always blow, and their reliability depended a lot on where in the world a ship was. But even assuming your ship wasn’t becalmed, getting your power from an external source made operating the ship far more complicated. Even a slight turn could be an intricate maneuver, requiring a ship’s many sails to be trimmed and adjusted to a precise degree.
A final issue was that the wind often blew in a direction other than where travelers wanted to go. Sometimes it blew in the opposite direction. A ship could mitigate this problem to some extent by adjusting the angle of its sails, but this method was limited. Special sails like the lateen and crab claw also helped, but once the wind was blowing directly against you, the only option was tacking. That basically means taking a zigzag course, cutting back and forth across the wind, like switchbacks on a really steep hill. As you can imagine, this took a long time.
This might sound like a joke if you don’t go in for nautical trivia, but I promise you that animal-powered boats were real. Every example I’ve found has used horses, but as far as I can tell, you could probably employ other beasts of burden if you wanted to.
The mechanism was fairly simple. Two horses walk on a flat, circular treadmill that connected to an axle. This axle connected to paddle wheels, usually one on either side of the vessel, which provided thrust. There was at least one experiment using screws instead of paddle wheels, but it didn’t go very far.
That sounds great since you got propulsion whenever you needed it, and you didn’t need all those people for rowing. So why didn’t everyone make use of this excellent mode of travel? For one thing, a treadmill that connected to an axle and in turn some paddle wheels was actually pretty advanced technology. It required a series of cranks and gears that many cultures simply didn’t have.
More importantly, this type of propulsion offered very little power. Horses were expensive and very large; it just wasn’t practical to put more than a handful on any one vessel. That’s why animal power was most often used on small river ferries. Speed wasn’t a big factor in these crossings, and the ferries didn’t have to fight against currents or the tide.
An alternate way to use animals in water travel was to have a horse, ox, or donkey on shore, pulling a boat or barge along with a rope. For larger craft, you might’ve used a team of animals. This only worked on exceptionally calm waters and was most often employed on canals.
What your watercraft is made of and how it is made are just as important as what powers it. In fact, the two are often linked. Sails can move truly massive ships, but that won’t work if your hull falls apart at that size.
For smaller vessels, there were a wide variety of materials available. Papyrus was once commonly used to make boats all around the Mediterranean and parts of Africa. It still is today, in fact, and it’s not hard to see why. Papyrus reeds were super buoyant, grew quickly in vast quantities, and could be shaped into a boat with little more than hand tools and twine. These reed boats served very well for fishing, personal transport, and light cargo hauling.
Animal skins were also a tried-and-true material, especially in environments where wood was scarce. First, a frame was constructed out of either animal bone or whatever wood was available, then skins were stretched over it. Add some waterproofing and you had sleek vessels ranging in size from one-person kayaks to 30-foot umiaks.*
Believe it or not, it was even possible to use metal, though this was historically rare. In the real world, iron-hulled sailing ships called windjammers didn’t come about until long after engines were commonplace. More likely, metal would be used as protection, either from cannon fire or from the sea itself. We think of ironclads as synonymous with steam engines, but Korean turtle ships had metal armor way back in the 1400s. Meanwhile, copper and lead sheaths have long been used to keep shipworms out of the hull.
But of course the gold standard of ship construction was always likely to be wood. Wood was strong, buoyant, and it literally grew on trees. When available, hardwoods like oak were usually the most prized type of wood for aquatic construction, as it was strong and resistant to water absorption. However, these hardwoods were expensive, and lower-quality woods were often used in their place. The “heart of oak” model was particularly popular, with important parts like the keel made of hardwood, and cheaper wood used to fill in the planking.
Once you’ve decided what your ships are made of, it’s time to consider how they are made. All ships are longer than they are wide, but the ratio is important. It’s a simple trade-off: narrower ships are faster, while wider ships can carry more.
Cargo ships would almost always favor capacity over speed unless they were carrying perishable goods. For passengers, it depended on wealth. Rich people could pay for a fast ship, while poorer voyagers were lucky to get a leaky tub. Speed tended to be a bigger factor for warships, but it wasn’t always emphasized. If cannons were commonplace, then carrying more guns might be more important than speed.
Speaking of speed, sharp v-shaped bows are more hydrodynamic, and it’s easy for western authors to imagine them as universal. That was not the case. A number of highly successful designs have used rounded or even square bows, such as the Korean panokseon and the great Chinese treasure ships. These designs reduced speed but tended to have greater stability and maneuverability.
A downside of wooden hulls was that wood absorbed water. Waterlogged hulls were leaky, heavier, and more likely to come apart in rough weather. If possible, hulls were sealed to slow the process down, usually with tar or pitch. However, that often wasn’t enough, and it was a common practice to beach smaller ships when they weren’t in use.
If you’re looking to get in the weeds of shipbuilding, you can consider whether the shipwrights in your world use the clinker or carvel method. In clinker construction, each plank of wood ran the ship’s entire length, and the planks overlapped each other for better waterproofing. This resulted in a ship that was both flexible and strong, but it also limited size. A clinker-built ship could only be as long as the trees used for its planking were tall. Lots of ships and boats have used this method, but you’re probably most familiar with the Viking longship, the most capable craft of its day.
Carvel construction, on the other hand, used pegs to join shorter planks together, and the planks didn’t overlap. The main advantage is that carvel-built ships could get much larger than their clinker cousins, since they were no longer limited by tree size. By the same token, carvel ships didn’t hold up so well in rough seas, and they were more difficult to waterproof.
Operating a Ship
The first thing to understand about ships is that they are ridiculously complex. You can easily drown your reader in nautical jargon about baggywrinkles, boom vangs, and hawsers. Would it mean anything if I told you to brace round forward or to clew up the mainsail? This applies even to seemingly straightforward aspects of maritime operation. Most people know what a sail is, but how many are prepared to learn the difference between royals, topsails, stunsails, and “the spanker”? Unless your story is really focused on the details, it’s usually best to gloss over exact terminology and stick with simpler language that the audience can understand.
Instead, the best practice is usually to bring across the feeling of operating a ship rather than the full wash of details. To that end, remember that ships took a lot of people working in tandem to operate. That’s true even today, and only gets more important with less automation. A small canoe or rowboat could be operated by a single person, but any larger than that and you need to think about coordination.
Large ships were not maneuvered simply by a captain at the wheel or steering oar. The entire crew had to act as one, and that required orders to be clearly understood by every sailor on board. On small ships, the captain could get by with just the power of their own voice, but on larger vessels that wasn’t enough. So how did you communicate orders from bow to stern without an intercom? Simple: A line of sailors who stood within shouting distance of each other, relaying the captain’s orders. This worked in reverse too. The captain depended on warnings from the ship’s lookout and other vital posts to determine a course.
For oared ships, it was important for every rower to be operating in tandem, especially for delicate and precise maneuvers. An officer set the rhythm, often by playing a beat on drums, and the ship’s overall speed was determined by how long the rowers can keep up a given pace.
Sail-powered ships were an order of magnitude more intricate. Remember, sails didn’t generate their own power; they picked it up from the wind. That meant a sailing vessel couldn’t just change the direction of its thrust the way a trireme could. Rudders and steering oars were still important, but just as important was adjusting the sails themselves.
Have you ever wondered about those countless feet of line* crisscrossing the deck of old tall ships? Most of those lines existed so the crew could adjust the sails when the ship was maneuvering. If the captain ordered a turn, the crew pulled on lines that turned the sails to catch just the right amount of wind. Depending on the turn, some sails would need to be furled up, while others were let down. If this wasn’t done correctly, then the best-case scenario was lost time as the ship wallowed about. The worst-case scenario was a collision or the ship capsizing as it took too much wind in the wrong direction.
These maneuvers got even more involved with close quarters or an uncooperative wind. My personal favorite is called boxhauling, where the ship temporarily goes into reverse to swing the bow around. There is plenty of material for exciting maneuvers on the high seas – just remember this isn’t something your main characters can do alone.
Crew and Passengers
One thing nearly all ships have in common is that they are crowded. Space is at a premium while at sea, and premodern vessels needed a lot of people to operate. Triremes needed such large crews that there was barely room for anything else on board. Sailing ships were a little roomier, but you’re still looking at a lot of people. Fully loaded, the USS Constitution carried a crew of around 450, while HMS Victory was closer to 850.
The conditions these sailors worked in depended largely on their cultural context. In ancient Greece, sailors were paid relatively well, and they were almost never slaves. On the other hand, later Mediterranean powers were happy to enslave anyone they could find to work the oars, which is where we get the term galley slave.
You might expect a nation’s reliance on its navy to improve conditions, but that often wasn’t the case. From the 1600s on, England, and later the United Kingdom, depended on its navy for power and prestige, but life aboard a British ship was so bad that the Royal Navy often pressed civilians into involuntary service.* We’re talking bad food, brutal discipline, and a high likelihood of never seeing home again.
Even in better circumstances, most sailors lived in extremely close quarters, usually sleeping in hammocks that dampened the ship’s constant rocking. Officers had it a little better, but private cabins were practically unheard of, reserved only for the captain or extremely wealthy passengers. It was almost always better to sleep on shore when possible, whether in actual lodgings or just camped on the beach.
For all that, a ship’s crew had to be skilled, or else the ship’s complex maneuvers would be impossible. Taking on a totally green crew was a real risk, even with experienced officers. Passengers were often called upon to work as well, and a skilled sailor might’ve been able to pay for a trip entirely with their labor.
Water and Nutrition
Without refrigeration, carrying provisions on a long voyage is difficult. River boats can at least stop to forage, but they still face all the difficulties of those who travel overland. Ships on open water have an extra problem: there is nowhere to stop for supplies unless you run into a handy island.
What’s more, water carried on board has a tendency to go bad quickly as numerous microbes take up residence. That’s why so many historical ships used beer or some other fermented drink, as the fermentation process kept microbes at bay for longer. Some ships practiced early forms of desalination, but this wasn’t very practical, mostly because evaporating water requires heat, and ships don’t have a lot of extra fuel lying around.
On long voyages, nearly all the food had to be preserved, with salted meat and hardtack biscuits being the mainstays of European crews. Sailors would fish when they could, but what they caught was usually little more than a supplement to their normal diet.
Getting enough calories could be a problem, but that’s nothing compared to the risk of insufficient nutrients, and that’s why we have to talk about scurvy. Without getting into the gory details, scurvy is a debilitating and deadly disease caused by a lack of vitamin C, something humans can’t synthesize on their own.
Most people past and present got their vitamin C from fresh fruits and vegetables, something it was notably difficult to bring on long voyages. Scurvy usually manifested in six to twelve weeks, so it wasn’t a big concern for short voyages, but you’ll have to consider it for anything longer.
The trick to scurvy is that it isn’t actually that hard to cure if you know what causes it. Citrus is one famous option, but there are plenty of others, most of them cheaper. Onion juice contains plenty of vitamin C, as do potatoes if your world has them. Both these options are easy to transport aboard ships, and that’s just scratching the surface.
So if the cure to scurvy is so simple, why was it such a huge problem historically? Mostly because it was a very difficult disease to investigate without modern technology, and historical researchers had no idea what they were looking for. The existence of vitamin C wasn’t proven until the 1930s, and the way scurvy manifests offered very little clue about its causes. Remember, it didn’t show up until at least six weeks after a patient has stopped getting vitamin C. With such a long delay, it’s no wonder that physicians didn’t immediately jump to the lack of vegetables as the cause.
Further, it was really easy to confuse the issue. Raw citrus juice would cure scurvy, but boiling it for safer storage destroyed most of the vitamin C, making the juice useless. Is it any wonder that so many sailors who got this ineffective cure concluded that the citrus angle must be bunk? If that wasn’t enough, numerous edge cases added more mud to the water. Many Inuit cultures lived on all-meat diets without ever getting scurvy, which seemed to discredit a lack of vegetables as the cause. What doctors of the time didn’t know is that the Inuit diet provided plenty of vitamin C through particular meats like caribou liver and seal brains, something a European sailor wasn’t likely to eat.
The Spruce Beer Question
Some of this controversy continues today, if you were wondering. There are numerous historical accounts claiming that spruce beer cured scurvy, and it seems to hold up on first glance. Spruce needles do contain a lot of vitamin C, after all. While researching this post, I came across several articles that accepted spruce beer as a cure for scurvy based on this reasoning. But it turns out that the fermentation process actually destroys most of the vitamin C, and what little is left leaches out after just a few days in storage.
So what’s the deal with all those historical accounts? I can’t say for sure, but my best guess is that they came from confusion over a spruce aqueous infusion, or spruce tea. This beverage retains a decent amount of vitamin C, and I’ve found a few accounts of Native Americans using it to get through the winter months when vegetables were scarce. They shared this knowledge with early European explorers, who figured that if spruce tea worked, spruce beer would be even better! From there, you can blame false positives. Any time someone who drank spruce beer didn’t get scurvy, it was thanks to the spruce beer. Anyone who drank spruce beer and did get scurvy was written off as an anomaly.
The good news for worldbuilders is that scurvy’s unusual nature makes it a completely optional disease. If you’re not interested in portraying its horrific effects, all you must do is describe how the sailors in your world drink a little onion juice to prevent bleeding of the gums. On the other hand, if ghastly illnesses are your jam, then you’ve got plenty of justification.
Navigating on the Water
Navigating without Google Maps is tricky no matter where you are, but water travel possesses some unique challenges. If you were traveling by river, you had all the normal difficulties of land navigation, plus the river itself could be a danger. Submerged obstacles weren’t always apparent until a boat ran up on one, so it was usually a good idea to send an advanced party to scout out any problems. If the river ever became impassable, the travelers had to decide whether to proceed on foot or carry their boats overland past the blockage.
For ocean voyages, there was a good chance travelers would do everything they could to keep sight of land. The shore offered something to navigate by and shelter from any rough weather that might come up, plus an opportunity to stop and resupply. But staying close to shore had its own problems. Shallow water meant the ship was more likely to strike a reef or shoal, especially at night when the coast itself was nearly invisible. That’s one reason lighthouses were so important: they let ships know where the shore was.
Following predictable routes within sight of land also made travelers much more vulnerable to attack, since any swashbuckling buccaneers knew just where to find them. These routes could also be really inefficient, taking ships far out of their way. But these costs were often worth it to avoid the difficulties of the open ocean.
These difficulties are many, most immediately that the ocean provides few landmarks. It’s just water as far as the eye can see. If travelers were lucky enough to have a magnetic compass, they could at least know what direction they were headed, and they could use the position of the sun to calculate their latitude. This wasn’t pleasant for the navigator, as it involved a lot of staring at the sun, but was doable. However, calculating longitude required an accurate clock that worked aboard the swaying deck of a ship, something that wasn’t invented in the real world until the mid 1700s.
Without a clock, travelers’ best option was called dead reckoning. Basically, they pointed the ship in the direction they wanted to go, then tried to sail in a completely straight line, keeping track of the ship’s longitude by measuring its speed. This method was usually accurate enough to get a ship across the Atlantic, but that’s about the best that can be said for it.
Another way to navigate that didn’t require longitude, latitude, or even compasses was to simply know the environment really well. This is how the Polynesians found their way, eventually building one of the farthest-reaching civilizations on Earth. You may have heard that Polynesian Wayfinders memorized the stars, and they did, but there was a lot more to it than that.
Through precise observation, the Wayfinders learned patterns in the ocean currents and used them to determine direction. They watched the undersides of distant clouds, and when the clouds turned brown, that signaled an island beyond the horizon. They even studied wildlife and could tell how close to land they were based on what birds or fish they encountered. This method requires a high degree of skill, but also familiarity with the area being navigated. It was less likely to work somewhere the navigator’s never been before.
In an age before engines, aquatic voyages were extremely difficult and fraught with danger. That may have been a drag for our ancestors, but it’s a great boon for us storytellers today. We can get all kinds of delicious conflict from just the mundane problems with ocean voyages, before we even think about adding magic or monsters. Now if I can just figure out how to write an Air Travel Before Engines post, we’ll have a complete set!
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