On the Alkalies of Commerce. G49 



It is easv to prevent any loss of weight in any of the 

 casks, hv care and celerity in the manipulation; during 

 which, iu danip seasons, a stove should be placed in the 

 tlore-room : if this precaution is not adopted, there will be 

 an increase of weight. 



Gradualhn of Sodas and Natron. 



It will not he difficult to apply these manipulations to 

 soda: this article must be first broken by means of a piece 

 of iror», then pounded in mortars, or bruised under a vertical 

 mill the stamper of which is inserted in a wooden axis : the 

 soda in powder must then be passed through a metallic sieve 

 for the convenience of those who use it. As soon as the 

 quantity is procured requisite to fill a given number of casks, 

 we must then proceed to make the general mixture above 

 described, and pursue the usual method, with the peculiar 

 modifications applicable to the trials upon soda. 



As to natron, the same method may be adapted as with 

 potash, with this exception, that, the masses being gene- 

 rally larger and harder, they require a little more time and 

 manipulation than potash. 



CEconomy of I he Graduat'ioti of ilie Alkalies of Commerce, 



Some people may be apprehensive that the expense of 

 these manipulations would counterbalance the advantages 

 to be derived from them ; but, after having made a gross 

 calculation of the expenses of this manipulation upon potash 

 and natron, I found they were very trilling; as to the ex- 

 penses upon the soda, these will be reduced one-half if we 

 deduct the expense of pulverization, which is, at all events, 

 an indispensable requisite with this article. 



Properly possessed by ike Alkali-meter of being used as a 

 BerthoUi-meter. 



I have the honour to transmit herewith to the academy a 

 tube at one and the same lime alkali-metrical andBertholli- 

 mctrical. The same scale serves for both, with this diffe- 

 rence, that the alkah-metrical scale is on the riglit side and 

 runs from top t© bottom, but the Bertholli-mcter is on 



the 



