16 BULLETIN 664, U. S. DEPARTMENT OF AGRICULTURE. 
is. however, a distinct difference, approximately 1.1 per cent, between 
the sound and the unsound eggs. This figure, applied to case lots of 
unsound eggs, shows an additional damage having a commercial im- 
portance. Applied, however, to the case of rehandled eggs as com- 
monly put up by the shipper, containing 19 with unsound shells, it 
amounts to only 0.2 egg per case, a neghgible number. Apparently, 
then, the matter of the 19 cracked eggs, as found in the well packed 
standard package, becomes an economic question of keeping quality 
in cold storage and of marketing, not of transportation damage. 
THE CHARACTER OF THE PACKAGE. 
Strength of cases.—In the course of this investigation the standard 
egg package was subjected to various tests? to determine the relative 
strength of the three kinds of wood (gum, tupelo, and cottonwood) 
commonly used, the number of nails needed, the manner in which the 
cases failed when subjected to evenly exerted pressures, and to obtain 
other data bearing on the subject. A summary of results, the details 
of which are too lengthy to be included here, is presented in this 
bulletin. Table 5 gives the average number of pounds of evenly 
applied pressure which the different cases withstood before they 
failed or became crushed. 
TABLE 5.—Analysis of strength of egg cases. 
Strength. 
Material. Type. ; Weight. 
f | Diagonal. ue Ls Pie Vertical. 
Pounds. | Pounds. 
Pounds. | Pounds. Pounds. 
GationwGod oto es eee 1a CAN ee | 5nails......_.. 590 2,214 9,810} 20,343 7. 25 
Radler nl sh. s Pe og ee done ae 567 2110| 13.629} 21,257 8. 89 
SRIDOLG see ee ee 5 ee) ed 1s ewe 0.2 en 687 1,914 
12,143 | 20, 294 8. 24 
| | | | 
In spite of greater weight, the gum and tupelo cases offer no addi- 
tional strength as compared with cottonwood. On the other hand, 
cottonwood presents certain advantages in that it is softer and 
odorless, and does not warp or crack as readily as the other woods. 
The results given in Table 5 are based on cases made up with 5 
cement-coated 3-penny nails at each corner of the sides and bot- 
tom and at the center partition. If only 4 cement-coated nails are 
used the package is weakened: this was also the case with smooth 
nails, even when 5 were used. The use of 6 cement-coated 5-penny 
nails slightly increases the rigidity of the case, an important fea-_ 
ture in safe transportation, since distortion of the case soon causes 
breakage. The same added rigidity is noticed when wire binding 
is used around the sides and bottom of the case at the ends; likewise 
when the lid is nailed in the center. . 
1The tests were made in cooperation with the Forest Products Laboratory, of the [Bilger st 
Department of Agriculture, and the Bureau of Standards, of the U. S. Department of 
Commerce. 
