SHELL-LESS EGGS. 199 



difficult for the reader to satisfy himself as to the 

 existence of animal matter and of lime in the shell. 

 If the shell is heated in the flame of a spirit lamp it 

 cracks and turns black, an effect due to the decar- 

 bonization of its animal constituents. A peculiar 

 smell is at the same time emitted, which is the 

 odour common to such matters when undergoing 

 combustion. The presence of lime may be deter- 

 mined by dissolving the egg-shell in dilute hydro- 

 chloric acid. If this solution is then poured into 

 a large quantity of water, and a few drops of a solu- 

 tion of oxalic acid are dropped into it, the white pre- 

 cipitate which immediately falls is oxalate of lim 



Sometimes eggs are laid without shells. Mr. 

 Jesse says, " If the leg of a pullet is broken 

 after she has laid two or three eggs, we find that 

 as long as there is necessity for the formation of 

 a new bone, she will perhaps drop one without 

 a shell, and then cease altogether from laying any 

 more till the bones of her leg are knit, and the 

 union is complete. From this it is clear that a 

 certain quantity of some material, lime and chalk 

 probably, is necessary to enable a hen to produce 

 a perfect egg." The lime in the case of the broken 

 bone was taken by the blood vessels to repair that 



