MAN ‘FROM THE’ FARTHESE ‘PAST 
Probably some accident led to the great discovery that 
heat would turn these curious stones soft and even make 
them run. A piece of gold fell into the fire and was 
melted; or a lump of copper ore was used along with other 
stones to make a fireplace, and turned soft in the heat. 
Nor should we ignore the probability that man, once he 
had reached a certain stage of intelligence, would deliber- 
ately make all sorts of experiments, Just to “see what 
would happen.” 
Pure copper is much more difficult to melt and cast 
successfully than when alloyed with certain other sub- 
Fic. 85. Flint-bladed dagger from the Neolithic village of Vinelz, Switzerland. 
From MacCurdy, after Tschumi 
stances. It happens that copper ores sometimes contain 
small quantities of arsenic, antimony, or tin, which when 
reduced will form natural alloys: so that chance no doubt 
led man to the discovery of how to make bronze. As one 
of the earliest alloys, man employed lead. Then he found 
that tin made a better one, and finally that the most satis- 
factory proportions were ninety per cent of copper and 
Fic. 86. Late Bronze Age sword, Switzerland. After Keller 
ten per cent of tin. This discovery ushered in the true 
Bronze Age, and it led to more far-reaching developments 
than the making of superior weapons and tools. For tin 
occurs in quantity in only a few places, and the demand 
for it perceptibly furthered the great extension of trade 
and migration and war, both by land and by sea, which we 
now know took place during the Bronze Age. 
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