﻿4 BULLETIN 17, U. S. DEPARTMENT OF AGRICULTURE. 



transporting perishable foodstuffs requiring more refrigeration than 

 is needed for fruit, much that is of interest to the packer, the carrier, 

 the middleman, and the consumer has been unearthed. It was 

 observed, for example, that different lots of poultry having identical 

 treatment before shipment, and approximately the same atmos- 

 pheric conditions during the haul, and requiring the same amount of 

 time to reach the market, arrived in widely varying states of preser- 

 vation. The differences were attributable, apparently, to the type of 

 car in which the journey was made. A study of the construction of 

 the cars in use on different lines revealed a marked variation both in 

 materials and in construction. Accordingly, those factors in car 

 construction on which efficiency of refrigeration depends were studied, 

 and the temperatures observed in the cars correlated, not only with 

 the preservation of the produce but with the construction of the car 

 as well. As was to be expected from previous work, the temperature 

 of the air in the different parts of the car was found to vary within 

 sufficiently wide limits to affect the stability of the flesh of the poul- 

 try. For example, that next to the side walls was quite unlike that 

 in the middle of the car. It was deemed advisable to obtain accurate 

 data on such variations, as well as on the fluctuations in the tempera- 

 ture of the air in the car, compared with the temperature changes 

 undergone by the poultry inside the packages. 



SCOPE OF THE INVESTIGATION. 



The experiments herein reported, covering the period between August, 

 1909, and October, 1912, include 120 car-lot shipments of dressed 

 poultry and aggregate 140,000 miles of haul. The hauls averaged 

 between 1,000 and 1,500 miles, terminating almost invariably in New 

 York City. No car was used twice, and six different car lines are 

 represented. The weather conditions varied, because the work con- 

 tinued from season to season, and the territory involved extended 

 from western Iowa to central Tennessee. 



The treatment which the produce received before shipment was 

 commercial, but represented the best methods in use. The cars were 

 those ordinarily received by the packer and in no case was a special 

 car used, nor was any difference made in the handling of the car en 

 route because it was under observation. Indeed, the railroads in 

 most instances did not know that the work was being done until 

 after it was finished. The information obtained at the market center 

 covered the usual routine of the unloading of the car, the holding of 

 the goods by the wholesaler for a short period, and its further deten- 

 tion by the retailer. In all of this part of the work commercial 

 surroundings and commercial routine prevailed; hence the facts which 

 follow may be accepted as indicative of the results of the practices 

 of that portion of the trade equipped to handle dressed poultry in 

 car lots or in smaller quantities. 



