Our Humble Helpers: Familiar Talks on the Domestic Animals

by Jean-Henri Fabre

“Either appearances deceive me greatly,” answered Louis, “or the shell is simply made of stone.”

“Yes, my friend, it is indeed of stone, but stone selected with exquisite care and refined as it were, in the bird’s body.

“In its nature the eggshell does not differ from common building-stone; or rather, on account of its extreme purity, it does not differ from the chalk that you use on the blackboard, or from the magnificent white marble that the sculptor seeks for the masterpieces of his chisel. Building-stone, marble, and chalk are at bottom the same substance, which is called lime, limestone, or carbonate of lime. The differences, [[31]]great as they may be, have to do with the state of purity and degree of consistency. That which building-stone contains in a state of impurity from other ingredients is contained also in white marble and chalk, but free from any admixture. Thus in its nature the eggshell is identical with chalk and marble, harder than the first, less hard than the second, being between the two in an intermediate state of pure lime. To clothe the egg, therefore, with a solid envelope, the hen and all birds without exception use the same material as the sculptor works with in his studio and the scholar uses on the blackboard.

“Now, no animal creates matter; none makes its body, with all that comes from it, out of nothing. The bird does not find within itself the material for the eggshell; it gets it from outside with its food. Amid the grain that is thrown to her the hen finds little bits of stone left there through imperfect cleaning; she swallows them without hesitation, knowing full well, however, that they are little stones and not kernels of wheat. That is not enough; you will see her all day long scratching and pecking here and there in the poultry-yard. Now and then she digs up some worm, her great delicacy, and from time to time some fragment of limestone, which she turns to account with as much satisfaction as if she had found a plump insect.”

“I have often seen hens swallowing little stones like that,” remarked Emile. “I thought it was all their own carelessness or gluttonous haste, but now [[32]]I begin to suspect the truth. Would not those little stones be useful in making the eggshell?”

“You are right, my little friend. The particles of lime swallowed with the food are converted into a fine pap, dissolved by the digestive action of the stomach. By a rigorous sorting the pure lime is separated from the rest, and it is made into a sort of chalk soup which at the right moment oozes around the egg and hardens into a shell. By swallowing little particles of lime, the hen, as you see, lays by materials for her eggshell. If these materials were wanting, if the food given her did not include lime, if, imprisoned in a cage, she could not procure carbonate of lime for herself by pecking in the ground, she would lay eggs without any shell and simply covered with a flabby skin.”

“Those soft eggs that hens sometimes lay come then from lack of lime?” asked Louis.

“They either come from the bird’s not having had the necessary carbonate of lime in her food or in the earth she pecked, or else her bad state of health did not permit the transformation of the little stones into that chalky pap which molds itself around the egg and becomes the shell. In countries where carbonate of lime is scarce in the soil, or even totally lacking, it is the custom to break up the eggshells and mix the coarse powder in the fowl’s food. It is a very judicious way of giving the hen in the most convenient form, the stony matter necessary for the perfect formation of the egg.”

“Sometimes,” observed Louis, “we find on the [[33]]dunghill eggs of a queer shape and as soft as hens’ eggs without the shell. Instead of a chicken, a snake comes out of them. They say they are laid by young cocks.”

“You are repeating now one of the false notions prevalent in the country—a foolish notion springing from a basis of actual fact. It is perfectly true that eggs soft, rather long, almost cylindrical, and of the same size at both ends, may be turned up by the fork as it stirs the warm manure of a dunghill. It is also perfectly true that from these eggs snakes are hatched, to the great surprise of the innocent person who thinks he sees there the product of some witchcraft. What is false is the supposed origin of the egg. Never, never has the cock, be he young or old, the faculty reserved exclusively for the hen, the faculty of laying. Those eggs found in dunghills, and remarkable for their strange shape, do not come from fowl; they are simply the eggs of a serpent, of an inoffensive snake which, when opportunity offers, buries its laying in the warm mass of a dunghill to aid the hatching. It is quite natural, then, that from serpents’ eggs serpents should hatch.”