278 § 14r2. beverages. 



centimetres of acid required for this represents the tem- 

 porary hardness. After adding the proper quantity of 

 nitric acid, proceed to add the standard solution of soap, 

 in the same manner as when determining the strength of 

 this solution with the aid of calcic sulphate. 



Suppose that, in treating 100 c.c. of the water in this 

 manner, 0.2 c.c. of nitric acid were required to produce a 

 permanent red color, and 8 c.c. of the solution of soap to 

 change the red to blue ; 2 c.c. of the latter were necessary 

 to decompose the calcic nitrate resulting from the actioii 

 of the 0.2 c.c. of nitric acid on the calcic carbonate, and 

 6 c.c. to decompose the calcic sulphate; subtracting 0.5 

 c.c, as above directed, for the excess of nitric acid, we 

 have 2° for the temporary hardness, and 5.5° for the per- 

 manent hardness of the water examined. 



10° of hardness indicates a hard water ; the hardness of 

 river water is usually from 2° to 6°. 



II. 



WINE. 



142. a. Specific Gravity,— Determine this carefully 

 with the specific-gravity bottle. 



1). Dry Substance in Solution. — Evaporate 20 grms. 

 to dryness with gypsum (§ 90, A). 



c. Total IVon-Yolatile Matters.— Evaporate 200-500 

 grms. to dryness on the water-bath, and incinerate the 

 residue in the usual manner ; determine carbonic acid in 

 the ash. 



d. Complete Analysis of the Ash.— This is rarely im- 

 portant, but may be made according to Scheme I., § 94. 



e. Protein Compounds, — Evaporate 100 grms. with 

 gypsum (§ 90, A), and ignite the residue with soda-lime 



(§ 85). 



