38 BULLETIN 898, U. S. DEPARTMENT OF AGRICULTURE. 
Grease spot.—Pour a little of the suspected turpentine on a piece of 
white writing paper. If the bulk of the sample evaporates rapidly 
from the paper, leaving a greasy spot which evaporates very slowly 
or not at all, the turpentine is probably adulterated with kerosene 
or heavy solvent naphtha, or contains a large percentage of heavy 
turpentine which will not distill below 170° C. The odor of the grease 
spot often determines the nature of the adulterant. Greasy spots 
around bung or spigot holes of turpentine barrels are also indicative 
of these adulterants. 
Bead.—When a perfectly clean dry bottle is partly filled with tur- 
pentine and violently shaken for a moment the bead or foam that 
forms will immediately pass away if the turpentine is pure and fresh, 
If the foam persists for 5 seconds or more, the turpentine probably 
is adulterated or old. 
Evaporation test—Set a 5-inch watch glass near an open window 
where a gentle air current can blow across it. Carefully place in it 
5 cc. (a tablespoonful) of the turpentine, so that the glass does not 
become wet with the turpentine beyond the edge of the surface of 
the liquid. Then carefully pipette or dip out 2 cc., or about half of it 
(a scant teaspoonful). Observe the rim of the turpentine film after 
3 hours. If the rim is continuous or more or less regular in outline, 
the turpentine is probably pure. If, however, the rim is made up of 
a chain of distinct drops or beads, or if the liquid appears to flow back 
to the center of the glass in distinct streams, it probably is adulter- 
ated with mineral oil or is an old turpentine of high specific gravity. 
The unevaporated residue will also smell of mineral oil if kerosene or 
any other oil which is less volatile than turpentine has been used 
as an adulterant. | 
Needless to state, if all these simple tests are definite, there can be 
little doubt that the turpentine is adulterated. When these tests are 
negative, however, it can not be safely assumed that it is not adul- 
terated to a small extent or very carefully to a large extent with a 
specially prepared turpentine adulterant or substitute. 
STATE LAWS GOVERNING TRANSACTIONS IN TURPENTINE. 
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State laws governing the sale of turpentine are in effect in 16 
States—California, Colorado, Florida, Georgia, Llinois, lowa, Kansas, 
Massachusetts, Michigan, Mississippi, New Jersey, New York, Ohio, 
Pennsylvania, Vermont, and Wisconsin. 
In Florida, Georgia, Iowa, Massachusetts, and Michigan the laws 
governing transactions in turpentine apply to no other material. In 
the other States such transactions are covered by the laws pertaining 
to paint or linseed oil. The number and date of each act, with a 
brief outline of the provisions pertaining to turpentine, follow: 
Florida (ch. 5115, No. 10, Acts of 1908, p. 44).—Known as the pure 
spirits of turpentine act. Defines turpentine or ‘“‘spirits of turpen- 
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