74 BULLETIX 51, U. S. DEPAETMEXT OE AGEICULTURE. 
contain millions of organisms. It is reasonable to conclude, there- 
fore, that the earlier forms of such and similar eggs furnish large 
numbers of bacteria to the liquid product prepared from second- 
grade food eggs. It is quite probable, also, that these earlier stages 
of incipient sour eggs are a contributing cause to the presence of 
appreciable numbers of B. coli in liquid Qgg of good quality. 
TECHNIQUE FOR THE BACTERIOLOGICAL EXAMINATION OF 
EGGS. 
METHODS USED FOR 0BTAIXEN:G SAMPLES OF IXDIYIDUAL EGGS 
OPENED ASEPTICALLY IN THE LABORATORY. 
A, Mercuric cldorld ni-etliod} — The eggs were washed in running 
water, treated for five minutes in a 1 to 500 or 1 to 1.000 mercuric 
chlorid solution, and then rinsed with sterile water. The Qgg was 
then placed, large end uppermost, in a suitable holder. A small open- 
ing was made in the ajDex with sterile, fine-pointed forceps, about 2 
square centimeters of the shell removed, and the membrane punc- 
tured. About 2 cc of the white were then transferred with a sterile 
pipette to a. sterile tared weighing flask containing small pieces of 
sterile glass. The opening was made larger and as much of the white 
as possible removed with the pipette. With a second sterile pipette 
the vitelline membrane was rux^tured. and about 2 cc of the yolk 
transferred to another weighing flask. '\'\Tien it was impossible to 
examine white and yolk separately, on account of disintegration, a 
sample of whole Qgg was taken. 
B. Flaming method.- — The Qgg was washed in running water, 
rinsed in sterile water, dried with a sterile towel, and placed, large 
end upjDermost, in a suitable holder. The top of the Qgg was steril- 
ized by flaming. A portion of the top was removed with fine-pointed 
forceps and the contents of the Qgg dropped into a sterile salt- 
rnouthed 4-ounce bottle containing sterile glass. 
PREPARATION OF COMPOSITE SAMPLES OF EGGS OPENED COMMER- 
CIALLY IN THE PACKING HOUSE. 
The details of the collection and handling of the samples are de- 
scribed on page 39. When the samples arrived in the morning, they 
were examined immediately. When they came late in the day, they 
were put at once into a sharp freezer and held overnight. On ar- 
rival at the laboratory the hard-frozen samples were placed imme- 
diately in a water bath at ^0^ C. and allowed to remain, with frequent 
shaking, until completely melted. After shaking the melted sample 
vigorously for Aat minutes, abofit 3 cc were transferred with a sterile 
pipette to a tared weighing flask. 
1 Samples 4001 to 4159, inclusive, and 3001 to 3030. inclusive, were obtained by this 
method. 
2 Samples with numbers under 1,000 were obtained bv this routine. 
