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Selected Articles. 
fthese however, the acid is extracted either from the Sorbus 
•or Sempervivum. As in the former of these plants it exists 
^almost entirely uncombined, while in the latter it is united 
with lime as a malate, a separate process is necessary for 
'each. In procuring the acid from the Sempervivum the ma- 
Jate is converted into a bi-malate by the addition of so much 
•sulphuric acid as will remove one half the lime, and then 
other operations upon the crystallized bi-malate, are neces- 
sary to separate the malic acid. From the comparative ease 
with which the bi-malate may be obtained from the berries 
of the Rhus, and the purity of the salt when procured in this 
way, there is no doubt that this fruit may be very advanta- 
geously employed in preparing malic acid for chemical pur- 
poses. I have as yet made no experiments to ascertain the 
amount of bi-malate which a given weight of the ripe berries 
of each of our species of Rhus will furnish, but I have no 
doubt that it would be found very considerable. Of the me- 
dicinal properties of the salt, I believe little or nothing is 
known. Should it have any value in this respect, or should 
its pleasant acidity bring it into general favour as an ingre- 
dient in our summer beverage, the great abundance of the 
plants in which it exists, would no doubt make it an object 
extensive manufacture. Amer. Jour.Sci. and Arts, 
