INFLUENCE ON LINSEED OIL OF SOURCE OF FLAX, ETC. 11 
during either season is identical. No. 19 produced the highest average 
yield, with No. 3 ranking second, followed in order by Nos. 12 and 
13 during both seasons. 
The annual average specific gravity of each Cereal Investigations 
number was lower in 1914 than in 1915. The ranking of the numbers 
with respect to specific gravity each year is very similar. Nos. 13 
and 3 possess the same relative high specific gravity each year and in 
general average are followed closely by Nos. 12 and 19. 
The 1914 oils were uniformly much higher in acid value than the 
1915 oils. In general average C. I. No. 19 was highest in acidity, 
followed by Nos. 12, 13, and 3. Much less difference is noted in 
the yearly average of the iodin values of the several oils. No. 
12 possessed the highest average iodin value during both years. 
No. 3 also occupied the same relative position during the two seasons. 
Arranged in decreasing order of their general average iodin value, the 
numbers rank as follows: 12, 13, 3, 19. 
In general average of drying it will be seen that C. I. No. 19 died 
the most rapidly, followed by Nos. 13, 12, and 3. This order was 
closely maintained during each season. 
Constant differences appear to exist in the four varieties in some 
of the physical and chemical properties. Thus, C. I. Nos. 19 and 3 
produced a constantly high yield of oil, while Nos. 12 and 13 pro- 
duced a constantly low yield. 
The specific gravity of C. I. No. 13 oils was constantly high at 
most of the stations during the period under observation, while No. 
19 oils were low in comparison in most cases. 
In acid value, C. I. No. 19 exceeded the other oils in most of the 
determinations during the two seasons. On the other hand No. 3 was 
constantly low in acid value. 
Considerable difference was noted in the iodin values of the several 
oils at the several stations during the two seasons. C. I. Nos. 12 
and 13 as a rule gave higher iodin values than Nos. 3 and 19, the 
latter being fairly constantly lower in this property. 
C. I. No. 19 excelled the other samples in the time of drying, fol- 
lowed closely by Nos. 13 and 12, with No. 3 showing the slowest dry- 
ing property during each year at nearly all of the stations. 
The drying of the oil does not seem to be solely dependent upon any 
one property of the oil. Rapidity of drying apparently depends 
upon a combination of properties. Thus, an oil combining high 
iodin value with high acid value dries comparatively rapidly. Like- 
wise, oils with high iodin values and high specific gravity also dry 
rapidly. Finally, oils combining high iodin values with high acidity 
and high specific gravity invariably dry very rapidly. 
In order to compare the various stations or geographical sources of 
the flax varieties with respect to yield and properties of the oil, the 
