MANUFACTURE OF PHOSPHORIC ACH). 
41 
which time over 4 tons of charge were smelted and tapped off as a 
molten slag, it is in excellent condition and ready for further experi- 
mentation. 
Views of this latest plant are shown in Plates VI to XL inclusive, 
and a plan view of the entire equipment is given in Figure 12. 
The data obtained in this three-day test, however, were not 
verv satisf actor v, owing to certain mechanical difficulties encoun- 
tered throughout the run and the poor quality of the fuel oil 
which was furnished. It is felt, therefore, that no fair approxi- 
mation of the proportion of fuel oil required to the amount of charge 
smelted can be made. 
The oil burners were started at 8.30 a. m., November 8. 1922. after 
a coke fire had been burning in the furnace shaft for several days. 
The cinder notches were closed and the first briquets added at 
