20 
BULLETIN 331, U. S. DEPARTMENT OF AGRICULTURE. 
Table VI. — Decay in carefully handled nonprecooled prunes immediately 
loaded and in those delayed two days in the warehouse oefore loading, Wil- 
lamette Valley, seasons of 1911 and 1913. 
Time factors and extent of decay (per cent). 
Season of 1911. 
Season of 1913. 
Time of inspection. 
Immediate 
shipment. 
Delayed 
shipment. 
Immediate 
shipment. 
Delayed 
shipment. 
10-day 
with- 
drawal. 
15-day 
with- 
drawal. 
10-dav 
with- 
drawal. 
15-day 
with- 
drawal. 
10-day 
with- 
drawal. 
15-day 
with- 
drawal. 
10-day 
with- 
drawal. 
15-day 
with- 
drawal. 
On withdrawal 
0.1 
1.8 
2.4 
0.1 
1.1 
3.6 
0.4 
2.1 
2.5 
1.7 
4.9 
4.5 
0.4 
3.0 
5.8 
1.2 
4.6 
8.7 
4.0 
10.0 
15.6 
6.4 
4 days after withdrawal 
13.8 
6 days after withdrawal 
20.4 
The data for 1913 emphasize even more strongly than the 1911 
data the necessity for prompt shipment. After a transit period of 
10 days the immediately loaded fruit showed on arrival 0A of 1 
per cent of decay and 5.8 per cent after a holding period of six days, 
as compared with 4 per cent of decay on arrival and 15.6 per cent 
at the end of a holding period of six days in the delayed fruit. The 
15-day withdrawals are equally consistent and show, of course, in 
the aggregate, more decay than the figures just given for the 10-day 
transit period. Where brown-rot is an important factor, as it was 
during 1913, prompt cooling and shipping is a prime necessity, and 
any considerable delay before cooling or shipping means the almost 
certain arrival of the fruit on the market in a very badly decayed 
condition. 
EFFECT OF PRECOOLING ON CARRYING QUALITY. 
The precooling experiments, as previously mentioned with cherries, 
were carried on in connection with a small precooling plant of 
1-carload capacity built by the Salem Fruit Union under the super- 
vision of the Bureau of Plant Industry. This plant was the first 
of its kind to be erected, and in it the principle of passing air 
directly through the mixture of ice and salt was adopted. The 
tank containing the refrigerating mixture is filled with crushed ice 
and salt, the air being passed through the bottom of the tank, and 
as the ice melts a new supply continually drops from the upper 
part of the tank. In this way the tank can be operated through an 
entire run without refilling. The precooling room is fitted with a 
false floor and return ducts, and by means of a fan the cool air is 
forced below the floor and through holes or openings in the false 
floor into the room, to circulate between the fruit packages stacked 
therein. The air is drawn back through the ceiling ducts to the ice 
tank and again circulated, the same air being used throughout the 
process. This method was utilized in the precooling experiments 
