Diodorus Siculus' chronicle of the Battle of Eknomos in 311BC:
"But when Hamilcar saw that his men were being overpowered and that
the Greeks in constantly increasing number were making their way into
the camp, he brought up his slingers, who came from the Balearic
Islands and numbered at least a thousand. By hurling a shower of great
stones, they wounded many and even killed not a few of those who were
attacking, and they shattered the defensive armour of most of them.
For these men, who are accustomed to sling stones weighing a mina,
contributed a great deal toward victory in battle, as they practised
constantly with the sling since childhood. In this way they drove the
Greeks from the camp and defeated them. Their equipment for fighting
consists of three slings, and of these they keep one around the head,
another around the belly, and the third in the hands. In the business
of war they hurl much larger stones than do any other slingers, and
with such force that the missile seems to have been shot, as it were,
from a catapult; consequently, in their assaults upon walled cities,
they strike the defenders on the battlements and disable them, and in
pitched battles they crush both shields and helmets and every kind of
protective armour. And they are so accurate in their aim that in the
majority of cases they never miss the target before them. The reason
for this is the continual practice which they get from childhood, in
that their mothers compel them, while still young boys, to use the
sling continually; for there is set up before them as a target a piece
of bread fastened to a stake, and the novice is not permitted to eat
until he has hit the bread, whereupon he takes it from his mother with
her permission and devours it!!".