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ANTHROPOLOGY: W, HOUGH 
the age of metals begins with the working of these naturally occurring 
substances by means of heat. The development of metallurgy has 
been the development of heat, resulting in remarkable inventions and 
achievements, and in the increase of temperature from that of the open 
camp-fire to the fierce heat of the blazing arc. Fire itself, the heritage 
of man through all ages, though adapted mostly to the advancement 
of man himself, had very limited use in the early periods, but the reac- 
tions of man on fire and of fire on man must have been profound. 
Metallurgy is impracticable without a concentration of heat beyond 
that furnished by a fire in the open suppKed with limited fuel. The 
first and natural step was to confine fire to a limited space demarked with 
stones or within a shallow earth-basin. Observations would show that 
the heart of the fire possesses greater heat than the margin and in an 
especially hot focus, one day when the time was ripe, a metal, likely 
copper, was tried and was found to melt and run without losing its 
structure. From such an event as that fancied here metallurgy may 
have had its crudest beginnings. The objection is noted that copper 
which liquidifies at 1083°C. would not melt ordinarily in an open- 
hearth fire under natural draught and this will be commented upon later 
in describing the efficiency of a smothered fire massed in an earth pit. 
Early experiments however were far from an established practice of 
metallurgy, a vast time may have elapsed before metals could be reduced 
from the ores. The history would begin with free metals regarded 
as stone and continue with metals (copper) hammered into shape; 
smelting of free metals (copper), and casting, followed by work in com- 
bined stone and metal technique; alloys both adventitious as in tin-bear- 
ing copper and designed as in the addition of cassiterite or oxide of tin 
to copper producing bronze. 
This imperfect resume covers a great advance in heat production to 
the time when a fourth metal, tin, becomes known to man. The 
bronze age with its ramifications of art, of science, and of material and 
social progress can only be characterized as a period when the cruder 
tentative essays in metals were brought to a somewhat exact metal- 
lurgical formula of pre-science. The Bronze Age also illustrates the 
vast importance of alloys. It more especially marks for the purpose of 
this paper the production and regulation of heat sufficient to smelt 
copper and tin forming the alloy known as bronze. 
It may be possible to trace the steps by which this heat was reached 
and it seems probable that its attainment depends on some other use 
of fire rather than for metallurgy. In this regard attention is called 
to the confinement of fire in a primitive oven for baking pottery or the 
