SANITARY CONTROL OF TOMATO-CANNING FACTORIES. 19 
parison tests also were made on some of the unsorted stock. The 
results of the tests from a few typical plants are shown graphically 
in figure 1. The tests at each factory are plotted in the order made, 
but they were not made at equal intervals. 
Factory No. 1 illustrates a case where the stock used was of very 
poor quality but, owing to the excellence of the sorting and washing 
systems, the decay was kept down to an average of 0.8 per cent, 
although two or three of the tests ran rather high. 
Factory No. 2, which had experienced trouble in producing a sani- 
tary product, Milopted i in 1916 a system of sorting and washing that 
very much improved the character of the product. In this case the 
average of the tests made for amount of rot was 0.5 per cent, with 
one test running up to the high point—for sorted stock—of 1.7 per 
cent. 
The table system of sorting was being followed at factory No. 3. 
The work, however, was done so ineffectively that tests on the sorted 
stock showed about 1.4 per cent of rot as against about 1.5 per cent 
for the unsorted, so that there was practically no improvement. The 
average amount of rot present was one and three-quarters times 
as much asin factory No. 1, although the condition of the unsorted 
stock at factory No. 1 was fourteen times as bad as at factory No. 3. 
At plant No. 4 the conditions as to sorting were found in 1910 to 
be very unsatisfactory. Since that time extensive experiments have 
been made, until in 1916 the improvement shown in the chart was 
observed. ‘The average of the seven tests made on two days was 
about 0.5 per cent. 
The chart also shows the result of tests made during three days 
at factory No.5. At the beginning of the experiment the plant had 
a number of serious defects in its sorting system. Later, several 
changes were made in the system and the factory was operated on a 
more approved method with striking results. The point when the 
changes were adopted is shown in figure 1 by the letter A. The 
average of the tests on the sorted stock prior to A was 1.26 per cent 
of rot; of the tests made subsequently, only 0.28 per cent. 
Data collected in many factories showed that in samples of un- 
sorted stock examined the percentage by weight of rotten material 
varied from practically nothing to over 30 per cent, while the aver- 
age in the whole series was about 5.5 per cent. The percentage of 
rot in the sorted stock (including the badly sorted as well as the 
thoroughly sorted) varied from practically zero to over 7 per cent, 
while the average was about 14 per cent. 
The percentage of rot by number was also determined during the 
season of 1916 in most places in addition to the percentage by weight. 
Although not so reliable as the determination by weight, it does at 
