}IAXUFACTTJRE OF PHOSPHORIC ACID. 
19 
THE USE OF THE FUEL FURNACE IN THE VOLATILIZATION OF 
PHOSPHORIC ACID. 
At the present time, however, there is very little cheap electric 
power available in this country. Moreover, the history of our hydro- 
electric developments in the past has shown that the demand for 
Fig. 
primary power for public utilities and for industries turning out 
relatively high-priced products has been so great that the manu- 
facturer of lower-priced goods which depend upon smelting processes 
has had to look to fuel for his source of energy. Even should there 
be a great increase in our power developments, many believe that it 
