﻿REFRIGERATION OF DRESSED POULTRY IN TRANSIT. 13 



low-temperature shipments increased to 0.0144 per cent, nearly the 

 same as the high-temperature shipments at the end of the transit 

 period. In other words, if the car temperature is above 35° F. the 

 poultry when it reaches the market has the disadvantage of a dete- 

 rioration equivalent to five or more days in the market, and to be in 

 the same state of freshness it must be consumed five days earlier than 

 that arriving at car temperatures below 26° F. 



These results give some idea of the effect of small differences in 

 temperature on poultry during the market period and indicate that 

 the most favorable temperature for poultry transportation is 30° F. 

 or below. It therefore becomes a fundamental problem in the 

 transportation of dressed poultry and similar products to maintain 

 low temperatures in all parts of the car, which finally resolves itself 

 into a question of car construction. 



REFRIGERATOR CARS. 



SOURCES OF DATA. 



The shipments already described and tabulated in Table 1 were 

 hauled by six different car lines. The cars were of so many different 

 series that they furnished a great variety of sizes, insulations, roofs, 

 doors, ice bunkers, and all of those elements which are factors in 

 the sum total of efficiency. 



The car number, the amount of ice and salt used in the initial 

 icing, the temperature of the car before and after loading, the posi- 

 tion of the thermographs, the prevailing atmospheric temperature 

 and weather conditions, the re-icing instructions, and the route were 

 all noted at the time of loading. A record of the movements of the 

 car's and the time and amount of ice and salt used in re-icing has 

 been generously furnished by the railroad companies. The railroads 

 have also greatly facilitated this study by freely providing detailed 

 blue prints showing the construction and insulation of the cars in 

 which the experimental shipments were carried. 



In some of the experiments the atmospheric temperature was 

 obtained by a thermograph fastened to the outside of the car. In 

 the majority, however, the average between the maximum and mini- 

 mum atmospheric temperatures was taken each day for the region 

 through which the car was passing, as shown by the daily weather 

 maps and monthly reviews issued by the United States Weather 

 Bureau. The temperature records obtained in this manner coincide 

 almost exactly with those obtained by thermograph on the outside 

 of the car. The inside car temperatures during transit were obtained 

 by thermographs. (See Table 4.) 



