BOUILLON. 79 



ployed, then, for the whole amount of 1 litre, just 100 

 times as much, minus that for the two samples used in 

 titration, will be needed. For example : To neutralize 

 10 c.c. of bouillon, 2 c.c. of the diluted (0.4 per cent.) 

 caustic soda solution were employed. For the remaining 

 980 c.c. of the litre of bouillon, then, 196 c.c. (200 c.c. 

 4 c.c., the amount employed for the two samples of 10 

 c.c. each of bouillon) is needed of the 0.4 per cent, solution, 

 or one-tenth of this amount of the 4 per cent, caustic soda 

 solution. 



For the neutralization of the whole bulk of the 

 bouillon it is better to employ the strong alkaline 

 solution, as by its use the volume is not increased to 

 so great an extent as when the dilute solution is used. 



It is evident that this method is much more exact 

 than that ordinarily employed, but at the same time it 

 must be remembered that for its success it requires ex- 

 actness in the measurement of the volumes, and the prep- 

 aration of the dilutions. To obviate error, it is better 

 to employ this method when the solutions are all cool 

 and of nearly the same temperature, so that rapid fluc- 

 tuations in temperature, and consequent alterations in 

 volume, will not materially interfere with the accuracy 

 of the results. 



This method of neutralization, which is employed by 

 Schultz, is to be recommended for those experiments in 

 which slight inaccuracies in the reaction of the media 

 play an important part. 



For the ordinary purposes of the beginner, however, 

 results quite satisfactory in their nature may be obtained 

 by the employment of the saturated sodium carbonate 

 solution for neutralization and litmus paper as the indi- 

 cator. For some time, however, it has been our practice 



