TURPENTINE. 3 
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down the face and is collected in galvanized-iron or baked-clay cups 
which hold from 1 to 2 quarts. About once a month these cups are 
‘“‘dipped”’ (PI. III, fig. 1) and the gum hauled to the still in barrels. 
A well-built still (Pl. III, fig. 2) saves labor and time, and prevents 
evaporation of turpentine from the gum, whereas an uncovered gum 
platform (Pl. IV, fig. 1) causes the dip barrels to leak and permits 
the evaporation of turpentine from the gum. 
The equipment used for distilling the turpentine from the gum or 
resin is simple, and has not been materially improved in the past 50 
or 60 years. It‘consists primarily of a large copper kettle, of from 
500 to 1,000 gallons capacity, connected by a still head (usually 
removable) to a large copper coil set in a large tub of water for con- 
densing the distillate. From 7 to 14 barrels of the crude gum are 
placed in the still, depending on the size of the still and also on the 
nature of the gum. Gum from third-year tappings froths more than 
virgin or first-year gum, for wee reason less of the older gum is put 
im the still at a time. 
The gum as it is placed in the still contains a small percentage of 
water, the presence of which lowers the temperature at which the 
turpentine will distill. At the beginning of the operation the dis- 
tillate consists of about 45 per cent of turpentine and 55 per cent of 
water. When nearly all the water originally present has been dis- 
tilled over, as shown by the decrease in the amount of water in the 
distillate to about 30 per cent and by the peculiar sound (termed the 
‘call for water’) heard on placing the ear close to the tail pipe of 
the condenser coil, a small stream of water is allowed to flow into the 
boiling gum in the still through an opening in the still head. Usually 
the mixture of turpentine and water is received in an open-headed 
barrel. The turpentine, being lighter than the water, rises to the 
top and is run off through a pipe into another open receiving barrel, 
from which it is either pumped to a storage tank or bailed into 
barrels, ready for shipment to the market. The water is allowed to 
flow out through an cpening at the bottom. When nearly all the tur- 
pentine has been distilled out, the flow of water is shut off, the still cap 
or head removed, and the molten rosin remaining in the still drawn 
from the still through an opening at the bottom. The yield of tur- 
pentine varies from 16 to 22 per cent of the original weight of the gum. 
The use of open separators and receiving barrels (Pl. V, fig. 1) is 
wasteful, as the turpentine, continually exposed to the air, evap- 
orates. This loss amounts to from one-fourth to three-fourths of 
a gallon for each charge, depending on the temperature at which 
the turpentine comes from the condenser and on atmospheric 
conditions, such as temperature, humidity, winds, etc. To over- 
come this unnecessary loss, turpentine producers should equip their 
stills with covered automatic separators and receiving barrels (PI. V, 
