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XLIX. Intelligence and Miscellaneous Articles. 



APPARATUS rOE THE DETERMINATION OF CARBONIC ACID, 

 BY MAX. SCHAFFNER. 



THIS is a modification of the apparatus of Will and Fresenius, 

 which may he weighed on 

 deUcate balances, and admits of 

 the determination of carbonic 

 acid with very great accuracy, 

 even when but small quantities 

 of the substance to be examined 

 can be employed. The figure i 

 shows it in natural size. 



A is a tube into which the 

 substance is introduced and 

 weighed. It is then moistened 

 with a little water, and the 

 tube closed with a cork, c, 

 through which pass two tubes, 

 ff and r, g passing through 

 the cork d closing the tube B, 

 which is filled with concen- 

 trated sulphuric acid as far as 

 is shown in the figure. The 

 tube g is closed by a piece of 

 glass rod s fitting into a caout- 

 chouc tube k. The tube i is 

 to allow the escape of the car- 

 bonic acid disengaged. The 

 whole apparatus may be hung 

 on the balance by the wire 

 hook h. 



When thus arranged and 

 weighed air is drawn through 

 i, the acid rises through the 

 tube r to the substance, and 

 the carbonic acid disengaged 

 is dried by passing through the 

 sulphuric acid. When the 

 effervescence has ceased, the 

 glass rod 5 is taken out, and 

 air drawn through the appa- 

 ratus at i to remove all the 

 carbonic acid. It is now 

 weighed again, and the loss of 

 weight gives the quantity of 

 carbonic acid. — Ann.der Chem. 

 und Pharm., vol. Ixxxii.p.335. 



