He discovered that the eggs after incubation remained suspended in the water for a space of from three to five days.
"Faces and Places"
Henry William Lucy
The operator, though he may have good eggs, may be neglectful or ignorant, and the health of the young birds seriously injured during the hours of incubation; or he may have a defective machine which under no condition can turn out healthy birds.
"Natural and Artificial Duck Culture"
James Rankin
Many of the manufacturers of incubators know very little about the first principles of artificial incubation.
"Natural and Artificial Duck Culture"
James Rankin