trade and exchange extended to
other tribes and groups until it was universally used. It is
interesting to note how many thousands of years this must have been the
chief weapon for destroying animals or crippling game at a distance.
Even as late as the Norman conquest, the bow-and-arrow was the chief
means of defense of the Anglo-Saxon yeoman, and for many previous
centuries in the historic period had been the chief implement in
warfare and in the chase. The use of the spear in fishing supplemented
that of the hook, and is found among all low-cultured tribes of the
present day. The American Indian will stand on a rock in the middle of
a stream, silently, for an hour if necessary, watching for a chance to
spear a salmon. These small devices were of tremendous importance in
increasing the food supply, and the making of them became a permanent
industry.

Along with the bow and arrow were developed many kinds of spears, axes,
and hammers, invented chiefly to be used in {88} war, but also used for
economic reasons. In the preparation of animal food, in the tanning of
skins, in the making of clothing, another set of stone implements was
developed. So, likewise, in the grinding of seeds, the mortar and
pestle were used, and the small hand-mill or grinder was devised. The
sign of the mortar and pestle at the front of drug-stores brings to
mind the fact that its first use was not for preparing medicines, but
for grinding grains and seeds.

_The Discovery and Use of Fire_.--The use of fire was practised in the
early history of man. Among the earliest records in caves are found
evidences of the use of fire. Charcoal is practically indestructible,
and, although it may be crushed, the small particles maintain their
shape in the clays and sands. In nearly all of the relics of man
discovered in caves, the evidences of fire are to be found, and no
living tribe has yet been discovered so low in the scale of life as to
be without the knowledge of fire and probably its simple uses, although
a few tribes have been for the time being without fire when first
discovered. This might seem to indicate that at a very early period
man did not know how to create fire artificially, but carried it and
preserved it in his wanderings. There are indications that a certain
individual was custodian of the fire, and later it was carried by the
priest or _cacique_. Here, as in other instances in the development of
the human race, an economic