272 



INTERNATIONAL CONGRESS OP VITICULTURE 



Time- 



From the curves above it would seem that added citric acid causes a 

 more even "sparkling." There is not such a marked first rush of gas, but 

 the rate of effervescence is steadier throughout. It is interesting to note that 

 the rate of effervescence during the last 20 minutes is in inverse proportion 

 to the total amount of gas given off up to that time. In every case the citric 

 acid appears to have caused a higher rate of effervescence at the end of one 

 hour than in the case of the witness. 



Series IV. The Effect of Tannin. 



The tannin was added in the form of a solution because only a slight 

 increase of tannin content was desired. The analyses are here tabulated. 



W WH 0<{ <!> CMS. PER 100 cc. 



W 



ACIDITY 



Iff SI 



o. : s 



Witness.. 1336.4 837.6 12.43 1.020 .050 .958 .990 3.02 2.13 .019 



