THE PRUNE 35 



the right texture of skin to stand this treatment 

 would be developed. 



This particular quality of skin would doubt- 

 less be subordinated when the plant migrated to 

 regions away from the salt water and crossed 

 with other races. But here as before the latent 

 trait would be preserved as a submerged heredi- 

 tary factor, ready when the occasion arose to 

 make itself again manifest. 



But how, it may not unnaturally be inquired, 

 would man himself discover the value of the 

 alkali bath in preserving the prune? 



Granted that a prune had been evolved 

 through artificial selection that had a sufficiently 

 high sugar content to make it a drying prune, 

 how chanced anyone to hit upon the particular 

 method of drying that is now employed, an es- 

 sential preliminary of which is the submersion 

 of the fruit in the alkali bath? 



The question is doubly pertinent because even 

 to this day in France the use of this method is 

 by no means universal. In many cases the prune 

 is still dried with the aid of artificial heat, the 

 fumes and smoke of wood or charcoal taking the 

 place of the alkali bath in giving the right qual- 

 ity to the skin and aiding in preservation. So we 

 may assume that the simpler method of using an 

 alkali bath is of very recent origin. 



