THE NAVAL STORES INDUSTRY. 29 
DISTILLATION PROCEDURE. 
The still is charged by removing the still head and gooseneck and 
dumping in the gum from the barrels. After most of the dip has 
run from the barrels they are thoroughly drained over a special 
trough. It is hard to remove the dip from the barrels during cold 
weather, and distillation is not carried on extensively in winter. 
When scrape is distilled alone, and the still is hot from the previous 
run, it is customary to pour in 5 or 6 buckets of water or a couple 
of barrels of dip to cool off the still and prevent the first scrape put in 
from " burning." 
After the still has been charged the cap is put on and connected 
with the worm by means of the gooseneck. The joints are then 
luted with clay. The fire is started under the still, and its intensity 
regulated solely by the peculiar noise made by the gum during dis- 
tillation. Crude gum always contains a certain amount of water 
(from 5 to 10 per cent), and since the gum melts rapidly, a mixture 
of oil and water soon appears at the end of the worm. A distilla- 
tion requires from 2 "to 2 J hours; all the water originally present 
distills over during the first one-half to three-fourths of an hour. 
The " stiller" follows the course of the distillation by placing his ear 
near the lower end of the worm, where the characteristic sounds made 
by the boiling gum are most audible, and by examining portions 
of the distillate collected in an ordinary drinking glass and noting 
the proportions of water and turpentine. The point at which addi- 
tional quantities of water should be added is indicated by a pecul- 
iar strident sound, characterized as the "call for water." 
The water added is obtained from the top of the cooling tank. It 
flows from a cock, by which the size of the stream is regulated, by 
way of a trough into the still through a funnel placed in an opening 
in the cap. The water at the top of the tank is always warm, and 
often very hot. Some distillers obtain this water from the bottom 
of the tank, claiming that the distillation is easier to regulate with 
cold water. About 2\ barrels of water are run in for each distilla- 
tion, the amount varying with the size of the charge. 
The critical period during distillation is passed when all the water 
in the gum has been driven over, since as the water is vaporized it 
swells the viscous gum to such an extent that it may overflow into 
the worm or escape through the joints, provided sufficient space has 
not been left in the still for this expansion. "Dip" and "scrape" 
from high faces are especially likely to boil over. The tendency to 
foam over is indicated by the sound of tumultuous boiling at the end 
of the worm. When this occurs the fire is urged as rapidly as pos- 
sible, the resinous chips obtained by skimming the gum usually 
being added, and the increased temperature maintained until the 
