TURPENTINE. 15 
tom delivery pipe, taking special care that the bottom valve of the 
car is closed tight and does not leak. While the car is being loaded 
the producer or seller should take a sample, as directed on page 44. 
This should not be neglected, as such samples are the seiler’s protec- 
tion against claims for adulteration, low grade, and noncompliance 
with specifications. The sample should be set away in a dark, cool 
piace in a full container until payment for the turpentine is received. 
Tf the turpentine has been sold on any definite specifications, a sealed 
portion of the sample in a fwil container should be forwarded for test, 
in accordance with the terms of the contract and specifications. 
Load the car until the shel! is completely filled, which can be done 
with certainty only when the car is perfectly level from end to end. © 
Record the temperature oi the turpentine at the bottom, middle, and 
near the top of the tank. Jt must be remembered that a tank car 
filled in the South may show an outage of several inches or more when 
ispected in the North, due to the difference in temperature between 
the shipping and receiving points. If the average temperature of the 
turpentine is above or below 60° F., the contraction or expansion 
which will take place on cooling or warming to that temperature can 
be determined. : 
Jt is advisable to load tank cars from storage tanks early in the 
morning during hot weather. ‘The turpentine is cool then, and the 
car will show less outage on arriving at its destination than it would 
if it had been loaded with warm turpentine. To allow for the con- 
traction in volume which usually occurs when turpentine is shipped 
from southern to northern points in tank cars, many shippers load 
the car several inches up into the dome, according to the tempera- 
ture. The higher the temperature of the turpentine when loaded, the 
higher in the dome the car should be filled. The total contraction 
for any difference in temperature may be determined as given in the 
specifications under “‘ Basis of Purchase”’ (p. 48). 
UNLOADING CARS. 
When ready to unload, the tank car should be exactly level, espe- 
cially from end to end, the outage carefully measured, and the tem- _ 
perature taken, as just directed. The bottom valve should then 
be opened slightly and any water contained in the car drained off 
and measured. After the water has been removed, connection 
should be made with a receiving tank and the valve opened wide. 
If the turpentine is to be tested for grade and purity, samples should 
be drawn while unloading, in general accordance with the instruc- 
tions given on page 44. © 
PAINTING THE INSIDE OF TURPENTINE TANKS AND TANK CARS. 
When in contact with iron for any length of time, especially if the 
tank is only partly full, turpentine gradually turns yellow. This is 
