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 simifar. 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 dr.'ed 

 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 



