ANTHROPOLOGY: W. HOUGH 
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cooking of vegetal substances, both very ancient arts and nearer to early 
needs than the working of metals. The cooking of vegetables in its 
primitive stage gives rise to ovens which may be ancestors of the furnace 
for reducing metals, namely the pit or ' gipsy' oven in which refractory 
fruits and vegetables were cooked. These pits were dug in the earth 
and heated by burning fuel in them, the coals removed and the vege- 
tables put in and covered up, a fire often being set on top. It is ob- 
served that in modern instances the heat produced by a fire of this char- 
acter is very great at the bottom of the glowing coals. There is a 
great concentration of heat due to the confinement of the fire in a non- 
conducting medium and this effect does not depend greatly upon excess 
oxygenation of the fuel by draught, in fact too much draught cools a 
fire. In such a fire bronze may easily be melted. There is used to this 
day a pit-smelter for melting bronze and this device would seem to be a 
survival. I saw one of these ovens in use in Washington a few years ago 
where it was employed for melting small portions of bronze for minor 
castings. European discoveries indicate that bronze was melted in 
pits in the earth and that the bronze founders had also acquired a knowl- 
edge of refractory clays which may have been contributed to some 
extent by the potter's art. It is evident that clay and metal working 
are intimately connected. 
The production of higher temperatures depends upon the oxygenation 
of the fuel beyond that ordinarily furnished by natural draught. Nat- 
ural draught in a forced fire fed with abundant fuel may give a central 
area of high temperature, but the question of fuel supply would mili- 
tate against the common employment of this method. The simple way 
in the earlier periods would be to aerate the fire with a fan-like hand- 
blower such as are used with the braseros and small cooking fires in many 
parts of the world. There would follow other devices to produce 
draught, culminating in the modern tremendous mechanical develop- 
ment for forced draught. Some steps on the way may be observed in 
the aboriginal pit ovens for cooking previously mentioned. Most of 
these are without draught holes or any device for producing draught, 
depending for their utility upon the absorption and retention of heat in 
the earth wall of the pit. The pit ovens of the Pueblo tribes have a 
draught flue alongside the pit. A step in advance involved in building 
separate fire containers is the raising of the fire and the production of 
bottom draught. To forced draught however we must look for prac- 
tical advance in metallurgy, and in comparatively recent times the use 
of preheated draught or blast was epoch making in the science of the 
production of metals. The forerunner of this was the tuyere embedded 
beneath the fire. 
