I collect dragons. I have more dragons in my collection than I have space to display them in the manner they deserve. Therefore, when it came time to do my visual aids speech back when I was earning my Competent Toastmaster award, I chose to base it on a book that I loved, The Flight of Dragons by Peter Dickinson. I think you’ll enjoy it. I had received the book as a Christmas present and I enjoyed reading it so much I actually finished it in about two days (I’m a slow reader, so that’s saying something).
Imagine yourself a traveling salt merchant on the coasts of England in times past. Today, you travels bring you to a seemingly deserted rural village. All the doors and windows are barred shut. There is a warm breeze, a bit too warm for this time of year. You keep on going, though, now you are more cautious. All the fields near the village are dry. As you get farther away from the village, the crops get blacker. Pretty soon they are nothing but ashes. Cattle are torn apart and strewn everywhere. Charred, black skeletons are all that is left of the dwellings. As you look upon this scene, your mind wonders to the legends you heard as a child. Stories of what had happened to villages like this. Tales of … dragons.
There are three ways of looking at the dragon:
1) They are completely legendary;
2) They are mostly legendary, but are created from second hand accounts of crocodiles and other large lizards; and
It would be irrational of me to invent anything new and expect you to believe this theory. So, I’m going to use what nature has already provided me with.
First, how big was a dragon? Through description in legends and literature, the average dragon can be said to be about 90 fit in length and about six feet thick. This estimate, of course, is putting everything I can in the dragon’s favor. Now let us assume that the dragon tapers evenly from this thickest point. This would give the dragon a volume of roughly 800 cubic feet. Excluding the weight of the wings, and putting to account that nature would apply weight saving strategies (such as hollow bones), the dragon would weigh somewhere around 20,000 lbs. Since the dragon didn’t have feathers, we won’t give him the lifting ability of a bird. We’ll give him the ability of a bumble bee, which holds the record for lift in the insect world.
If we give the dragon a normal type of wing shape, he would need 16,000 square feed of wing to lift 40,000 lbs. This would give the dragon a wing span of 600 feet. A creature like this could not fly, it would be aerodynamically impossible.
Yet, according to legend, the dragon did fly. He was able to hover and could fly at great speeds. An example of this speed would be the journey the dragon Smaug took from Lonely Mountain to Laketown in J.R.R. Tolkien’s The Hobbit. He only took the first half of a night, while it took Bilbo and the dwarfs three days (in the opposite direction).
Even if we reduce the dragon’s length and increase the wing efficiency beyond anything else known, the dragon still can’t fly. What does this leave us with, then? Weight. To be able to fly, the dragon had to be almost weightless.
Man’s history of aviation proves that lighter-than-air flying methods are the simplest.
While the dinosaurs were experimenting with horns and frills, the protodragon was becoming lighter and lighter. They probably leapt after their prey. The leaps became longer and longer. The leaping became gliding. The gliding in turn became flying.
The lighter-than-air vehicles, like the Hindenburg, could fly only because they were big. The dragon’s body was hollow and filled with lighter-than-air gas. He had to be enormous, otherwise he wouldn’t be able to hold enough gas to provide the lift for the total weight of the beast.
The dragon’s body was filled with Hydrogen. Helium couldn’t have been used because it is an inert gas, not commonly found in compounds of nature. Hydrogen, though is a very light, abundant gas. It is in a substance common in the digestive system of all vertebrates — hydrochloric acid. When combined with calcium, found in the bones, the acid reacts to form hydrogen gas.
The dragon’s body would be divided up into bone cavities with muscular membranes separating them. A resistant mucus would coat anything which would need protection from the acid. Acid glads would open, releasing the acid so it would flow down the walls of the cavity reacting with the calcium. The bone would be self-renewing continually. Flight was achieved by controlled digestion of the bone structure.
Normally pressure in the cavities would be mild, causing the dragon to be light, but not buoyant. When the dragon wished to fly, his membranes would relax and the volume of hydrogen would expand. The dragon would become buoyant in the air, because his mass would be the same but, his volume would increase. A fish’s swim bladder works in a similar way.
The spines down the dragon’s back were a protective cover for the expanded membranes.
This would also explain why the body was able to remain rigid in flight. The body was self-supporting and didn’t rely on wings to hold it up. His wings were small because they were only needed for propulsion and maneuvering.
Now that we know how they flew, we come to the problem of the fiery breath. The breath of fire wasn’t another mechanism, but a necessary part of the dragon’s mode of flight.
The dragon spent a lot of its time in caves sleeping. If the dragon didn’t burn his breath the hydrogen gas he expelled would form an extremely explosive atmosphere in the cave. So how did he ignite the hydrogen gas? An electrical spark would be unlikely because the only creature which is able to do this is specialized in this one thing. The dragon is already specialized, so a chemical ignition system would be more probable. There is such a system in a living creature today. The bombardier beetle is capable of spitting a liquid of several hundred degrees for protection. This is achieved by two separate glands which shoot out the chemicals which combine only when clear of the beetle’s mouth. So, somehow, the dragon added some kind of chemical which caused a spontaneous combustion when the hydrogen got clear of the dragon’s mouth.
No fossils will be found to prove any of this theory because when the dragon dies this hydrogen producing system would go on unchecked corroding the skeleton away to nothing before it could become fossilized.
Let’s return to our friend the salt merchant. He continues on his way, making a sign of the cross. The sky is darkening as the red sun starts to dip behind the hills. Suddenly a shadow covers him from overhead.
I believe in dragons. Do you?