85

Employ mermaid escorts. They are smart. They like stuff we have because they accept it in payment from ships crossing their territory. Presumably they can deal with criminals of their own kind. Mermaids associated with the area in question accompany boats. They ward off rouge mermaids whom they identify by their ruddy complexions. The mermaid escorts (...


20

I am surprized nobody mentioned lack of materials. Lack of coal or metals would prevent most machinery from being made. In addition, use of any fossil fuel in a closed environment of a cave will quickly deplete oxygent. Maybe somebody tried it early on, and since then, fires are no longer allowed. Dragon's fire breath is not a fossil fuel, it uses methane ...


19

Surely you are just thinking of something like this? That there is an Amphibious Assault Ship. A large part of its role is to carry, launch and service a fleet of smaller ships (and helicopters)


17

A giant catamaran. A top view: ____________________________________________________ / \ / Starboard hull \ | Bow Stern | \ ____ ____ ____ ____ ____ ____ / \__/ \__/ \__/ \__/ \__/ ...


12

These dragons are the original ones who colonized the cave. Yes: they are 3.5 million years old. Actually 3.85, 3.97, 4.12 and Gramps at 5.193 million years old. Dragons are not very creative because they don't need to be and your cave dwellers are especially uncreative because their quiet cave environment offers no impetus to try new things. Moving into ...


11

Torpedo boat carrier These things were actually done in real life with torpedo boats and larger ships which carried them out to sea. One example of such vessel would be the La Foudre (later converted to a sea plane carrier. The same principles can be applied here, provided the Hunter ships are small enough in relation to the carrier and the cranes you have ...


10

Bomb fishing While your post specifies medieval technology, that does not inherently exclude gunpowder, which was described as early as the 13th century, even in Europe. While sophisticated cannons and firearms are likely unreasonable stretches, simple explosive shells with timed fuses should be entirely doable. While black powder is not a high explosive, ...


8

Forget the wake by avoiding it altogether The idea of having a huge, hollow ship is unrealistic even in a fantasy setting. Aircraft carriers are made out of steel and not English Oak because ships that size require the advantages of steel and mighty engines to exist. You didn't say whether or not your ships are made of steel or depend on combustion. So let's ...


7

There's no such thing as an unarmed spaceship. Any spaceship with decent mass (about the kiloton mark) and going at a noticeable fraction of the speed of light can become a relativistic kill missile just by crashing at its high speed. Now being a magically enhanced sea ship, your ships will be lighter than that and thus a little less devastating, but not ...


7

I approach this by thinking about contemporary whaling ships, and then thinking about how one could add to that technology. The first thing that comes to my mind is giant crossbow harpoons with drogues attached; the drogues would keep the mermaids from diving and tire them out (as they did for whalers). You could assume that the nations of the time would ...


7

Dragons are mentally incapable of grasping how to read/write This could maybe be explained by severe dyslexia, blindness, or possibly even the inability to mentally comprehend language itself. The big turning point for mankind coming out of the stone age was literacy. For over a million years, man kind's ancestors survived by learning what they could from ...


7

Your race is very conservative and nature-loving Intelligent dragons are not like people. They prefer solitary life, see trade as nothing more than a necessary evil, and, above all, protect the state of their natural habitat. Defacing their land is one of the most heinous crimes to them, so, building a factory or a railroad is nearly as bad as killing ...


7

Where minting was done by hammering bullion to a plate of a certain thickness first, then cutting it in circles, and then hammering these circles with the stamp. As far as I know, it did not exactly work it that way. The minting was done with a piece of metal of the requisite weight, put into a "coin anvil" maybe one inch deep. The anvil was often ...


7

Large predatory animals such as griffons would likely naturally disperse to any suitable habitat, mostly as younger individuals without a territory leave their parent's nest and set out on their own. This is how, for example, black bears, mountain lions, and coyotes have spread across much of North America after being removed from much of their ancestral ...


7

Symbiosis: I think the real critical question is "How do you entice humans to build nests for griffins to live in?" Large, aggressive apex predators don't generally get along well with humans. If, on the other hand, you had a pacifistic (possibly even vegetarian) intelligent species that needed protection (imagine halflings), they could raise sheep ...


6

Mermaid hostages Maybe mermaids don't attack their own kind, or if their own kind are under threat. The ships may keep young or smaller mermaids aboard, under threat of killing them if the ship is attacked. Or perhaps some mermaids serve as members of the crew (or entertainment) beyond just being a hostage/prisoner. Of course it seems like the true answer ...


6

You exposed their attack methods in your previous question: This presents a problem as a group of giant mermaids could capsize a cargo ship and steal its loot. Once the ship is capsized the attack is over. This can indeed be easily achieved by a coordinated attack: some of them holding onto a side of the ship to add an unbalanced load while others push the ...


6

If the mermaids can survive an extended period out of the water then sling some hammocks across the interior of a wagon. They can ride in what is probably the most comfortable position for a mermaid on dry land.. lying down. The humans could provide buckets of water and rags or sponges so the mermaids can moisten themselves if needed during the day. At night ...


6

Sedan Chair For most things a sort of Sedan chair or litter would be the preferred mode of overland transport. Swim upriver until you reach your destination city/town, hire a litter from the docks, and get quickly carried to your destination. This would be especially good if your merpeople are comfortable in a "sitting" position and if they don't ...


6

It might not be as difficult as you imagine. In the early part of the medieval period, communal bathing was relatively common. The church fought against this, of course, but it took them quite some time before they actually managed to start affecting the practice. It is also worth noting that something akin to a bikini was already worn much earlier in the ...


5

Are these mermaids susceptible to poison? Toxins? Ships could carry a cargo of substances dangerous to mermaids and dump these into the surrounding water when under attack or even just if being scouted out. Or they might coat darts or other weapons with the poison/toxin and have at it (presumably there would be people especially trained to use these ...


5

The UNDO program. In a decent magic novel whose name escapes me, the protagonist was a programmer with small magical talent who built up magic spells like programs from small parts. To ensure nothing would go wrong, he designed his magic UNDO program first. The dragons did something similar. They progressed for a few years or a few months, until a magic ...


4

Religion/tradition/principles/evolution Technological stagnation has happened before. Although there obviously was scientific progress in some areas, during the European medieval period much groundbreaking work was suppressed by the church, often discouraging or even killing the researchers. But in many other countries, you see slow or stagnant progress. ...


4

Weakspots under the sea A famous Dutch story tells how one sailor heroically jumped over board, swam to the enemy ship and drilled some holes while clinging to it to make it sink. If memory serves correctly, the captain had some beef with the sailor and didn't save the sailir from the water afterwards. The story shows something important. The vulnerability ...


4

Most Merfolk will Travel Using Crutches There are a lot of answers here based on what merfolk of considerable wealth could choose from, but the idea of persons of normal means owning any sort of vehicles is a pretty new concept. Instead, consider that merfolk are basically no different on land than a 1-legged human. The use of wooden crutches as a means for ...


4

You are approaching this issue in the completely wrong way. Ethology is the study of animal behavior (e.g. how does a wolf pack hunt deer). Ecology is the study of populations (e.g. how does a wolf pack affect a herd of deer). Because you got these two confused, you are literally looking at the wrong information. Take for example: Chompers/Anklebiters: I ...


3

Degeneration: Your dragons aren't as smart as their ancestors were. Why, after all, should they be? They've been living in a totally stable environment for millions of years. There is no great drive to have tech, and no advantage to having tech. There isn't even an advantage to being intelligent, except agriculture. The time spent learning science and ...


3

Based on what we know about other marine mammals: Sound travels more efficiently (faster and farther) in water than air, so it seems that medieval tech could produce a loud enough noise to disrupt them, particularly if they have sensitive hearing. https://www.sciencealert.com/this-is-the-horrifying-reason-why-sonar-makes-beaked-whales-beach-themselves ...


3

What Is Your Magic Based On? Do you have to be born with a gift (like the wizards in Harry Potter)? Can everybody learn magic? (Maybe with a little natural talent involved, like music or complicated mathematics or any craft; a simple fire spell might be as common as matches!) Maybe there are different kinds of magic in different parts of the world, either ...


3

A common concept in Magic is the use of familiars - an animal with which the caster has an extra-sensory connection. Using the Raven example from chasly's answer, if a mute person has the aptitude for magic, they are paired with a familiar capable of speech. They then use their extrasensory (psychic) link to speak through the familiar. This provides the ...


Only top voted, non community-wiki answers of a minimum length are eligible