or eastern markets should be properly refrigerated or heated in accordance with 
prevailing weather conditions. Thermostatically controlled mechanically re- 
frigerated trucks and trailers with adequate insulation are preferred to ice- 
refrigerated units. Some mechanical systems are designed to heat as well as 
cool. Thermostatically controlled liquid fuel heaters are available for pro- 
tecting against cold (11). Proper loading of trucks and trailers to prevent 
excessive bruising and container damage is described by Johnson and Breakiron 
(2) « 
Rail Shipments 
The majority of long distance shipments are still made in rail refriger- 
ator cars, especially from the west coast. Equipment available includes ice- 
refrigerated fan cars, thermostatically controlled fan cars with ice refriger- 
ation, and mechanical cars capable of both refrigerating and heating. Mechan- 
ically equipped truck-rail (piggyback) trailers operated by the railroads are 
rapidly becoming available. They offer many of the advantages of the over-the- 
road trucks, such as door-to-door delivery and reduced handling. 
The protective services available for rail shipments include refriger- 
ation, ventilation, and heating (12). The use of car fans to obtain more 
uniform temperatures is very important under both refrigeration and heater 
service in providing more uniform temperatures throughout the load (6, 12, 13, 
14, 15, 18). Fisher and Smith (3) state that ventilation service is suReIEied 
only with apples that are intended for immediate use, because of the lack of 
temperature control under this service. Otherwise, cars should move with vents 
closed. Liquid fuel (LF) heaters with thermostatic control have been adopted 
as standard equipment by most of the railroads in the United States as a result 
of extensive tests conducted cooperatively by the U. S. Department of Agricul- 
ture and the Association of American Railroads (AAR) (13, 14). In thermostat- 
ically controlled fan cars (Ice Tempco) the desired temperature is set on the 
thermostat while the car is under refrigeration. When it is used with LF 
heaters, the heater thermostat is used for control. In mechanical cars, the 
railroad sets the thermostat to provide the desired transit temperature, whether 
under refrigeration or heat. 
Containers and Loading 2) 
Many new containers are now available for apples; they are described 
elsewhere in this publication. One of the purposes of an adequate container is 
to protect the commodity from damage while in transit. Proper loading patterns 
are required to prevent container damage and also to provide adequate air cir- 
culation for proper temperature control. 
Recommended methods of loading various containers in refrigerated trail- 
ers are illustrated by Johnson and Breakiron in Agriculture Handbook 105 (9). 
A comprehensive study of truck shipments of McIntosh apples from New England to 
Florida is reported by Shadburne (16). He found that the containers should be 
of uniform size to minimize container damage. To prevent damage from containers 
2/ See also section on Shipping Containers and Consumer Packages. 
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