BOOK X. Lxxiv. 149-LXXV. 152 



chick already alive is heard inside the shell. At the 

 same time it begins to grow feathers, its posture 

 being such that it has its head above its right foot 

 but its right vving above its head. The yolk graduall}'^ 

 disappears. All birds are born feet first, the opposite 

 way to the remaining animals. Some domestic hens 

 lay all their eggs in pairs, and according to CorneHus 

 Celsus occasionally hatch twin chicks, one larger 

 than the other ; though some assert that twin 

 chicks are never hatched out. They lay down a 

 rule that the hen should not be required to sit on 

 more than 25 eggs at a time. Hens begin to lay at 

 midwinter, and breed best before the spring equinox : 

 chickens born after midsummer do not attain the 

 proper size, and the later they are hatched the more 

 they fall short of it. 



LXXV. It pays best for eggs to be sat on within RnUs for 

 ten days of laying ; older or fresher ones are infertile. ^ting^hena. 

 An odd number should be put under the hen. If 

 three days after they began to be sat on the top of 

 the eggs held in the tips of the fingers against the 

 Hght shows a transparent colour of a single hue, the 

 eggs are judged to be barren. and others should be 

 substituted for them. They may also be tested in 

 water : an empty egg floats, and consequently people 

 prefer eggs that sink, that is, are full, to put under 

 the hens. But they warn against their being tested 

 by shaking, on the ground that if the vital veins are 

 displaced the eggs are sterile. The ninth" day after 

 a new moon is assigned for starting a hens sitting, 

 as eggs begun earher do not hatch out. The chicks 

 are hatched more quickly when the days are warm, 

 and consequently eggs will hatch out in 18 days in 

 summer but 24 in winter. If it thunders while the 



389 



