94 BULLETIN 1115, U. S. DEPARTMENT OF AGRICULTURE. 
There is a marked difference in the rate of change in the samples 
attributable to the types of containers. The samples stored in the 
metal drums showed practically no change. The change in those 
stored in the other containers varied from a very slight one, in 
the case of the tightest hardwood barrels, to a marked one in the 
case of the more open containers, such as sugar barrels. For the 
hardwood barrels the average increase in water-soluble arsenic oxid 
after 12 months was 0.06 per cent (maximum, 0.31 per cent) and 
in carbon dioxid, 0.85 per cent; at the end of 20 months, the average 
increase was 0.15 per cent in soluble arsenic oxid (maximum, 0.53 
per cent) and 1.40 per cent in carbon dioxid. The samples stored 
in the paper-lined and unlined veneer drums showed little difference. 
At the end of 12 months the average increase in soluble arsenic 
oxid was 0.15 per cent (maximum, 0.55 per cent) and in carbon 
dioxid 1.38 per cent. After 20 months the average increase in 
soluble arsenic oxid was 0.30 per cent (maximum, 0.65 per cent) 
and in carbon dioxid 2.21 per cent. In the lined and unlined sugar 
barrels the average increase in soluble arsenic oxid after 12 months 
was 0.31 per cent (maximum, 0.57 per cent) and in carbon dioxid 
1.72 per cent. After 20 months the soluble arsenic oxid increase 
averaged 0.45 per cent (maximum, 0.63 per cent) and the carbon 
dioxid increase averaged 2.01 per cent. 
The average results showing the behavior of the material stored in 
the different containers are given in Table 3 and Figures 47, 48, 49, 
and 50. Each curve represents the average of the products of dif- 
ferent manufacturers contained in packages of the same type. Four 
types of containers, metal drum (1), paper-lined sugar barrel (3), 
hardwood barrel (4), and paper-lined veneer drum (6), are repre- 
sented under the six brands* included in the subdivision tests, and 
all of these (23 subdivisions) were subsampled on exactly the same 
dates. Each type of container is treated separately in order to 
bring out the parallelism between the carbon dioxid and water- 
soluble arsenic changes, and two graphs, showing all four curves for 
carbon dioxid and for arsenic oxid, respectively, are presented in 
Figures 51 and 52. 
8 Only five brands are represented in the case of the paper-lined barrels. 
