12 
BULLETIN" 601, U. S. DEPARTMENT OF AGRICULTURE. 
at the end of the 6-day holding period, while that commercially cut 
showed a little over 40 per cent — less than half as much. 
The effect of precooling is shown best in the commercially cut 
lettuce. In the precooled lots practically all the lettuce was in 
marketable condition at the end of the 6-day holding period, and 
70.9 per cent was prime, while the nonprecooled lots showed an 
average of 6.7 per cent of worthless lettuce and only 40.1 per cent 
prime. The high temperature at which the lettuce was held after 
its withdrawal from the refrigerator car caused it to decay very 
rapidly, as the lower part of figure 8 plainly indicates. The amount 
of worthless lettuce in the various lots three days after their with- 
drawal from the car is particularly worth noting. Contrasting one 
extreme of handling with the other, as shown in figure 8, the pre- 
cooled carefully handled lettuce showed 10 per cent worthless and 
65.6 per cent prime, whereas the nonprecooled commercially handled 
lettuce showed 48.7 per cent worthless and 3.4 per cent prime. 
Table IV. — Average percentages of decay in sixteen experimental lots of carefully cut and 
commercially cut lettuce held six days in an iced car at Palmetto, Fla., during the 
season of 1913-14. 
At withdrawal. 
Three days after witddrawal. 
Treatment. 
Carefully 
cut. 
Commer- 
cially cut. 
Repacked. 
Undisturbed. 
Carefully 
cut. 
Commer- 
cially cut. 
Carefully 
cut. 
Commer- 
cially cut. 
Nonprecooled: 
Heads showing slight drop-rot, 
per cent. 
8.6 
1.4 
36.2 
22.5 
27.1 
25.5 
25.6 
69.2 
22.9 
30 
19.8 
Heads showing bad drop-rot. per cent. . 
73.8 
Total drop-rot i do. . 
10 ' 
58.7 
52.6 
94.8 
52.9 
93.6 
Heads showing bacterial rot do . . 
. 
2.4 
7.5 
5.8 
7.8 
9.2 
Precooled: 
Heads showing slight drop-rot, 
1.6 

24 
4.5 
14.6 
11.1 
36.5 
41.8 
22.6 
13.7 
25 
Heads showing bad drop-rot. per cent. . 
57.3 
Total drop-rot do.. 
1.6 
28.5 
25.7 
78.3 
36.3 
82.3 
Heads showing bacterial rot do. . 

. 7 
2.6 
3.4 
6.4 
8.5 
i In some cases both drop and bacterial decay "were found on the same head. As these diseases were 
recorded separately, the total of all forms of decay may appear to amount to more than 100 per cent 
in some instances. 
A glance at Table IV and the diagram shown in figure 9 gives a 
convincing impression of the effect of precooling and of careful cut- 
ting upon the development of decay. In the carefully cut non- 
precooled lots only 10 per cent showed serious signs of drop-rot at 
the first inspection, at which time the comparable commercially 
handled lots showed 58.7 per cent. In the carefully cut precooled 
lots, the drop-rot was so slight as to be of almost no commercial im- 
portance, whereas in the commercially cut nonprecooled lots more 
