214 THE POULTRY-BOOK. 



There is another method of preserving eggs a long while 

 fresh, depending on very different principles from the pre- 

 ceding, but well worth notice. We are indebted for the dis- 

 covery, if indeed it may be termed one, to the same ingenious 

 French experimenter, M. Reaumur. Having remarked that 

 there was a very great difference among eggs as to the rapid- 

 ity with which they became unfit for use and putrid, he inves- 

 tigated the causes of this difference, and found that it was the 

 eggs which had not been rendered reproductive by the cock, 

 that continue long uncorrupted. 



In order, therefore, to have eggs to keep fresh from spring 

 to the middle or even the end of winter, it is only necessary to 

 deprive the hens of all communication with cocks, for at least 

 a month before the eggs are put away. Without knowing 

 this, people often find, among the eggs they buy, some which 

 soon spoil, and others that will keep for a long time. 



Mr. Dickson also says that eggs keep well when pre- 

 served in salt, by arranging them in a barrel first, a layer 

 of salt, and then a layer of eggs, alternately. This can only, 

 however, act mechanically, like bran or saw-dust, so long as 

 the salt continues dry, for in that case the chlorine, which is 

 the antiseptic principle of the salt, is not evolved. When the 

 salt, however, becomes damp, its preservative principle will be 

 brought into action, and may penetrate through the pores of 

 the shell. 



The dealers are reported to have recently discovered that 

 immersing eggs in vitriol or sulphuric acid is a very effectual 

 means of preservation, and it is very probable it is so ; for the 

 sulphuric acid will act chemically on the carbonate of lime in 

 the shell, by setting free the carbonic acid gas, while it unites 

 with the lime, and forms sulphate of lime, or plaster of Paris. 

 The pores of the shell will in this way be closed up with plas- 

 ter of Paris, and in a more minute and effectual way, too, than 

 could be done by its direct application. 



