Today, a cannon that's two hundred years too old.
The University of Houston's College of Engineering
presents this series about the machines that make
our civilization run, and the people whose
ingenuity created them.
We used to think that the
oldest cannons were the medieval bombards. They
looked like big cast-iron pots. In fact, the French
called them pots de fer, literally,
pots of iron. They were pear-shaped with a
narrow neck and a flared top. The oldest one we
know is shown in a 1327 French manuscript. A knight
in armor is applying a red-hot poker to its fuse. A
spear-shaped projectile is about to be launched
from its neck.
Historians have argued over the source of firearms.
Before 1327 they find ambiguous hints of Arabic,
Chinese, and European guns. We've found remains of
a Chinese handgun from 39 years be-fore that French
bombard picture. Old writings in the West mention
earlier ordnance that might've used explosives.
But, at best, they too go back only into the late
1200's.
In 1985 a visitor to a Buddhist cave in the Chinese
province of Szechuan noticed something that other
people had missed. There, carved on opposing walls,
are groups of figures, eight of whom are armed to
the teeth. One is a horned demon, holding what is
unmistakably a bombard -- just like the
one in the French drawing. Another holds a bomb.
Both carvings are unambiguous. They even show
flames exploding outward.
But there's a catch. These figures were carved in
1128 -- two centuries before the French
bombard. Another interesting wrinkle: these figures
form a kind of heavenly host. They stand on clouds
and they include angels, armed and unarmed humans,
as well as six demons. Only the demons hold the
firearms.
A group of historians now offers this cave as
evidence that the cannon went from China to Europe.
And we must wonder why anything so important took
so long to make the trip? They come to an odd
conclusion. You need a lot of saltpeter to make
good gunpowder, and the best source of medieval
saltpeter was animal manure.
China had fewer domesticated animals than Europe,
and the Chinese managed their use of animal waste
and manure differently. The result was that
saltpeter was harder to come by for the Chinese.
Their gunpowder was made with too little saltpeter
to be very powerful. Perhaps the bombard spread
slowly in China because it was not a very effective
weapon there.
The last crowning irony of these carvings is the
intent of the cave itself. It was meant to
propagate its builders' prayers for permanent
peace. Inscriptions express the prayer "that
weapons of war be forever stilled." The
figures on the walls display all the weapons that
the sculptors hoped would never be used.
Eventually, however, the bombards did come out of
the cave, and out of China. Western armorers loaded
them with far better powder and made them into a
terrible weapon. This 850-year-old prayer for
permanent peace reveals the beginnings of slaughter
on a scale that those Buddhist monks could never
have imagined.
I'm John Lienhard, at the University of Houston,
where we're interested in the way inventive minds
work.
(Theme music)
G-d Lu, J. Needham, and C-h Phan, The Oldest
Representation of a Bombard. Technology and
Culture, Vol. 29, No. 3, 1988, pp. 594-605.
This is a greatly reworked version of Episode 242.

Fifteenth-century Spanish canon called a
caterara (clipart
image)
The Engines of Our Ingenuity is
Copyright © 1988-2002 by John H.
Lienhard.