﻿26 



BULLETIN 17, U. S. DEPARTMENT OF AGRICULTURE. 



in this shipment, the whole car being warmer than is a good refrig- 

 erator, even at the bunker. It seems impossible during warm weather 

 to reduce the air at the center of thinly insulated cars to the tem- 

 perature best suited to the transportation of dressed poultry. 



EFFECT OF CAPACITY. 



The cars of type D, which are the most efficient of those studied, 

 are likewise the smallest in point of cubic capacity. The total 

 available space in these cars is about 1,640 cubic feet. Type C 

 provides about 1,833 cubic feet of space, but with this increased 



_^ loading capacity 



15? 



h 



there is a decrease in 

 the power to main- 

 tain low tempera- 

 tures. Type C, how- 

 ever, has one-half 

 inch less insulation 

 on the roof than type D. The cars of 

 type B, which reduce the roof insulation 

 by still another one-half inch, offer about 

 2,050 cubic feet of space, but at a big 

 sacrifice in efficiency. Type A, with the 

 same insulation as type B, is smaller, 

 1,909 cubic feet, and is correspondingly 

 higher in efficiency. 



Another type of car, with insulation 

 as represented in figure 5, / (sides), fig- 

 ure 6, d (roof), and figure 7, e (floor), has 

 an available space of 2,010 cubic feet. 



Even with the 

 three layers of 

 one-half inch 

 insulation 



Fig. 11. — Iron tank bunker used in type D car. thr O U 2"hout 



there is a wide difference in temperature between the center and 

 ends of the car during warm weather (fig. 14). From this figure it 

 is evident that, in the very large cars, one and one-half inches of 

 insulation is not enough to insure the best temperatures for poultry 

 transportation while comparatively high atmospheric temperatures 

 prevail. Figure 15 gives temperature records in cars insulated, 

 as shown in figure 5, e (sides), figure 6, e (roof), and figure 7, / (floor). 

 These cars are of the large type, but with the 2 inches of insulation 

 on the roof the interior temperatures at the bunker were fairly 

 satisfactory. 



The results, as a whole, indicate that large cars require additional 

 insulation to yield the same efficiency as the small cars. 



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