REFRIGERATION OF DRESSED POULTRY IN TRANSIT. 
21 
presents a general openness. Type B, with the same thickness of 
insulation, is more compact, but does not have the upturned edges 
to protect the corners (fig. 6, 6). Type C is characterized by a heavy 
layer of hair felt, 1| inches thick, packed closely between the ceiling 
and subceiling with no intervening air space (fig. 6, c). In figure 
6, d, is shown a roof with insulation of the same thickness as the 
preceding one, but separated into three layers with intervening air 
spaces. Figure 6, e, represents a roof with 2 inches of hair felt insula- 
tion, each of the two layers being protected on both sides with 
•poop 
PUPL/A/E 
SUB-PUPUA/E 
'PEtT POOP/A/G 
SUB-POOP 
£ " L/A/OPELT 
/AJSULATtOA/ 
£ "L/A/.0/=£ZT 
CE/L/A/G 
-/Poor 
SC/B-POOP 
'PCPL/A/E 
/A/SOL A T/OA/ 
PAIPEP 
r "ha/PPELT 
j^PAPEP 
CE/L/A/G 
poop 
</P SPACE 
/ "HA/A? PELT, 
SUB- CE/L/A/G 
A//? SPACE 
/'/-/A/PPELT 
OB- CE/L/A/G 
A/P SPACE 
CE/L/A/G 
PAPEP 
poop 
Pt/PL/A/E 
SOB-POPL/A/E 
SOB- POOS?" 
HA/P PELT 
/A/SULAT/OA/ 
'PAPEP 
■^"/-/Ai/P PELT 
CE/L/A/G 
POOP 
POPL/A/E 
SUB-PUPL/NE 
UB-POOP 
HA/P PELT 
/A/SC/LAT/OA/ 
PELT 
PAPEP 
'/A/SULAT/OA/ 
PAPEP 
E/L/A/G 
Fig. 6.— Cross sections showing roof insulation of different types of refrigerator cars: a, Type A; b, type B; 
c, type C; d, roof insulation separated into three layers; e, roof insulation with 2 inches of hair felt; 
/,typeD. 
insulation paper. Type D (fig. 6, /) also has two thicknesses of 
1-inch hair felt, with the additional precaution of upturned edges. 
Floor. — The floors of types A and B (fig. 7, a, b) are equipped with 
two thicknesses of half-inch insulation separated by air spaces. 
Types C, D, and F (fig. 7, c, d,f) have one layer 1 inch thick, and type 
E (fig. 7, e) has three layers one-half inch thick, with well-protected 
joints. 
Comparison. — There is but very little difference in the side-wall 
insulation of the four types of cars whose efficiency indices are 
given in Table 5. Each type is provided with 1 inch of the non- 
conducting material. Although the insulation of A and B is 
divided into two half -inch layers in contrast to the single 1-inch 
