When we looked at designing a ship for a fantasy novel, I chose a 15th century carrack. It was a good choice. It has the right look, has all the DNA of more modern sailing ships and could be used for trading or warfare. It has occurred to me, however, that there is another ancient craft that would work well as a warship in either a fantasy novel or if reworked as a steampunk warship.
I am referring to the legendary Greek trireme of the 5th century BCE, a 100 foot long galley propelled by three banks of oars. The ships were light, fast and deadly. A bronze ram at the bow could sink enemy ships and soldiers on the trireme could also capture other ships by boarding. One hundred and seventy highly trained sailors manned the oars. The ships were light enough to be beached and carried ashore by the crew.
The trireme was designed specifically for the Aegean and the Mediterranean seas, where the winds were often light, and the water could be quite shallow around and between islands. In heavier seas, the galleys became unmanageable, but in the more sheltered waters of the Aegean and the Mediterranean, galleys continue to be used for the next 1,500 years.
Many historians, however, considered the trireme to be legendary in both the figurative and literal sense of the word. Many viewed the ancient accounts of the speed and maneuverability of the trireme to be wildly exaggerated. Some even referred to the trireme as “mythological.” The question was finally put to rest in 1987 when Olympias, a full scale trireme was built and tested and proved to be as fast and manueverable as the ancient texts suggested.
The Trireme in Fantasy Novels
The trireme could be adapted directly for a fantasy novel. It would make a great imperial galley. One does not need to be limited to three banks of oars. From the trireme the quadrireme, the quinquereme, and hexareme, and septireme were also developed. Add as many banks of oars as you see fit.
A Steam Punk Trireme
It occurs to me that a trireme could have a place in steam punk. As a start, replace the 170 rowers with a boiler, two reciprocating steam engines, connecting rods, cams and bearings. The trireme should row with just a handful of engineers and stokers. Weight and trim would be an issue. You would probably want the machinery placed amidships to maintain the trim. The ship could be built out of aluminum, light gauge steel or soft wood over a steel frame, similar to composite built ships, like the Cutty Sark. A metal trireme could be considerably larger than the pine and oak trireme of old.
Now, if a writer gets creative, a steam punk trireme could be really fun. For example, what if the oars were made to be articulating, able to hinge down like an insect’s leg? The ship could become amphibious, rising up off the beach and marching inland like a huge caterpillar with a ram on its nose. (The fairly simple connecting rods and cams just got a lot more complicated, of course.)
If you want to go even crazier, why not make the trireme fly? Put an air handler on the boiler and pump hot air into a rather large blimp deployed over the length of the deck. Voila! Would it work? Probably not. No matter how light you made the trireme, it would probably still be too heavy to be lifted by a hot air balloon. Then again, we are discussing fiction, so what matters is less whether the engineering works, but whether the writer can convince the reader that it does.
Clarion Blog 
Great ideas! This ship could be adapted for many uses, even sci fi.
Or – now here’s an idea, give the Steampunk trireme wings. Spread out a canvas over the oars and have the engines flap them. With the aid of a hot air (or Hydrogen or Helium!) balloon, we can finally have our flying triremes.
It’s probably no more realistically feasible. But hey, I like wings!
Ships like the Cutty Sark did not have soft wood hulls. Wooden hulls were usually oak, although in the Napoleonic War period the Royal Navy built some ships in India out of mahogany. Ship masts were pine because (a) it was cheap, (b) pine is flexible, a desirable trait in masts, and (c) pine trees generally grow straight, requiring little work to covert into masts.