Thersites said:
Guthrie: You're right about someone with a crossbow learning to hit a target from a reasonable distance quite quickly, but the bows which were decisive in battles were composite bows and the longbow and the only people who could fire those at all, let alone accurately, had to begin learning as children. When the wreck of the Mary Rose, Henry VIII's warship, was brought up the archaeologists could tell the archers by the deformities of their bodies.
I don't know about the Chinese, but the Romans had crossbows too, but they were very heavy weapons used in sieges- given the weight of pull they were probably accurate enough to use as sniper weapons. Where did you find out about the Chinese? Certainly the history of China, being repeatedly invaded by horse-riding nomads, makes it even odder that they didn't develop effective cavalry: is central Chinese territory- the traditional heartlands of China- unsuitable for horse breeding perhaps?
I am not totally sold on composite bows and longbows being the only bows decisvie in battle. Why else were the so popular, even if the genoese/ milanese (I forget which) crossbowmen the french hired not much use in the hundred years war. At various times, crossbows could certainly pierce most armour, just as much as longbows could (though it also depended on which head was being used, range, angle, etc.) But at other times they had arrow proof armour.
I read about the CHinese in at least 2 different books, the idea being that the use of the crossbow gave an advantage to peasants and masses greater than that of having a knight on a horse, and since horses were a bit smaller, they had poorer armour, and probably the entire imperial ethos, it just wasnt worth develioping a heavy cavalry of knights, which were a pretty local western invention anyway, that necessitated the use of stirrups (which were 7th century AD I think) and a lot of land ot support the knights and the horses. Knights were expensive.
As for muskets versus bows, the actual composition of armies changed over time. During the 1460's to 1480's war of the roses, armies were over half archers, the rest were billmen, pole axe armed knights in armour, etc. Meanwhile on the continent, halberds and pikes were developing, and these were good against cavalry. Over the medieval period, teh main arm of battle changed from being a heavily armed knight with a few supporters tagging along, into masses of men armed with pole weapons, against which men on horses have little chance. However, if you then match up cavalry, pikes and archers, you have a robust and flexible force that is very capable.
Anyway, where I was going was to say that it was masses that counted. Even in the 17th century english civil war, the main mass of the army was pikemen. They also had musket men, one of whose purposes was to drive off cavalry, who were usually reduced to firing their pistols into the ranks of pikemen.
Anyway, the resons for the decline in longbow are complex, but essentially revolve around the expense of the bows, arrows and trained men, and the evolution of the gun as an effective weapon.
As for the MAry Rose skeletons, they had I think incredibly well developed left shoulders and arms. They also worked out that some of the bows went up to about 185 pounds pull! Which doenst mean much to most people, but I've used 40 pound pull bows quite a bit, and tried 80 pounds, and could hardly bend it. No wonder they were deformed.